Non-destructive testing (NDT) has long been a cornerstone in ensuring the integrity and safety of structures, components, and materials across various industries. As technology advances, the integration of nanotechnology into NDT has opened up new frontiers, offering unprecedented levels of precision, sensitivity, and efficiency. This article provides an overview of the convergence of non-destructive testing and nanotechnology, exploring the innovative techniques, applications, and potential impact on diverse sectors.
Non-destructive Testing (NDT)
Non-destructive testing encompasses a range of techniques designed to evaluate the properties of materials without causing damage. These methods are crucial for identifying defects, assessing structural integrity, and ensuring the reliability of critical components. Traditional NDT methods include ultrasonic testing, radiography, magnetic particle testing, and eddy current testing. While these methods have proven effective, the marriage of NDT and nanotechnology is poised to revolutionize the field.
Nanotechnology in NDT
Nanotechnology involves manipulating materials at the nanoscale, typically at dimensions of less than 100 nanometers. When applied to NDT, nanotechnology brings a wealth of advantages, including enhanced sensitivity, improved resolution, and the ability to detect defects at a microscopic level. Here are key ways in which nanotechnology is making an impact in non-destructive testing.
Enhanced Imaging Resolution
Nanomaterials, such as nanoparticles and nanocomposites, enable the development of advanced imaging agents. These agents, when incorporated into NDT methods like radiography or magnetic resonance imaging, enhance resolution and provide detailed insights into the internal structure of materials.
Sensitivity Improvement
Nanoscale sensors and probes enhance the sensitivity of NDT techniques. For instance, nano sensors can be employed in ultrasonic testing to detect minute defects or irregularities that may go unnoticed with conventional sensors. This heightened sensitivity contributes to early defect detection and prevention.
Functional Nanomaterials
Functional nanomaterials, like carbon nanotubes or quantum dots, are employed to tailor specific properties for NDT applications. Carbon nanotubes, for example, can be used in sensors to improve conductivity and responsiveness, making them valuable for detecting flaws in materials.
Smart Coatings
Nanotechnology enables the development of smart coatings that respond to external stimuli, such as changes in temperature or stress. These coatings, when applied to surfaces, can reveal hidden defects or structural changes, providing real-time data during operation without disrupting the material’s integrity.
Applications of Nanotechnology in NDT
The incorporation of nanotechnology into non-destructive testing has resulted in a myriad of applications across diverse industries. Some notable areas where this synergy is making a significant impact include:
Aerospace Industry
In the aerospace sector, where the demand for lightweight yet robust materials is critical, nanotechnology aids in identifying defects at the nanoscale. This ensures the integrity of components like aircraft wings and fuselage, contributing to overall safety and efficiency.
Medical Imaging
In the field of medical imaging, the use of nanomaterials enhances the resolution of diagnostic tools. Nanoparticles can be employed as contrast agents in techniques like magnetic resonance imaging (MRI) or ultrasound, allowing for more accurate and detailed medical assessments.
Materials Science and Manufacturing
Nanotechnology plays a pivotal role in materials science and manufacturing, where the detection of microscopic defects is crucial. Whether assessing welds in construction materials or inspecting microelectronics in manufacturing processes, nanotechnology-driven NDT ensures the quality and reliability of products.
Oil and Gas Industry
In the oil and gas sector, nanotechnology aids in the inspection of pipelines and critical infrastructure. Nano sensors can detect corrosion or structural weaknesses in real-time, preventing potential disasters and optimizing maintenance schedules.
Challenges and Future Directions
While the integration of nanotechnology into NDT holds immense promise, there are challenges that researchers and industries must address. Ensuring the scalability and cost-effectiveness of nanotechnology-driven NDT methods, as well as addressing potential environmental and health concerns related to nanomaterials, are crucial aspects.
The future of NDT with nanotechnology is likely to witness further innovations, including the development of autonomous nanorobots for in-situ inspections and the application of artificial intelligence to analyze complex nanoscale data. As research progresses, the synergy between non-destructive testing and nanotechnology will continue to redefine the boundaries of material inspection and quality assurance.
Conclusion
The convergence of non-destructive testing and nanotechnology represents a paradigm shift in how we assess the integrity of materials and structures. Nanotechnology’s ability to operate at the molecular and atomic levels brings unprecedented precision and sensitivity to NDT methods, ensuring early defect detection and contributing to enhanced safety across industries. As research and development in this field advance, the innovative applications of nanotechnology in NDT are poised to reshape industry standards, making material inspection more reliable, efficient, and technologically sophisticated.
Finding the right solution for your heavy-duty load-bearing tasks can sometimes feel like a daunting mission. Yet, help is at hand with the effective and comprehensive option of heavy-duty steel trestles. This article aims to serve as an informative guide to understanding heavy duty trestles, their uses, and benefits.
In the wider sphere of construction, a trestle is referred to as the framework consisting of a horizontal beam supported by two pairs of sloping legs. Steel trestles specifically possess commendable robustness and resilience, which makes them ideal for intensive industrial applications. When we delve into the realm of heavy-duty steel trestles, we are introduced to remarkable strength and a higher load-bearing capacity.
A heavy-duty steel trestle not just stands as a symbol of strength and durability but also promotes high functionality in various applications. They can support substantial weight, thereby acting as a perfect solution for various tasks that require load-bearing.
Heavy-duty steel trestles serve as indispensable tools in various industries, demonstrating their adaptability in fields ranging from construction and mining to automotive and heavy industries. Their primary function is to provide robust support for a multitude of applications, including scaffolds, formwork structures, pipes, containers, machinery, and even bridges. This versatility allows them to cater to diverse needs beyond mere structural support, making them valuable assets in the industrial landscape.
2. Assisting Assembly and Disassembly
These steel trestles go beyond static support roles by actively participating in the assembly and disassembly processes within manufacturing units. They facilitate tasks such as equipment setup, component assembly, and maintenance activities. Additionally, their utility extends to tasks like painting structures, where they provide temporary support to workers, ensuring safe and accessible work surfaces for painting and coating applications.
3. Customization for Specific Requirements
One of the standout features of heavy-duty steel trestles is their customizability. They can be adjusted and tailored to meet specific project requirements, which enhances their adaptability and broadens their scope of applications. This customization capability ensures that they can effectively support a wide range of industrial and construction-related tasks, making them a versatile solution.
4. Temporary Work Platforms at Construction Sites
Construction sites often employ heavy-duty steel trestles to create temporary elevated work platforms. These platforms offer elevated workspaces for construction workers while allowing unobstructed movement beneath them. By providing such elevated spaces, steel trestles promote a more efficient workflow at construction sites, improving accessibility and contributing to streamlined construction procedures.
5. Promoting Safety and Efficiency
The use of heavy-duty steel trestles at construction sites enhances both safety and efficiency. They offer a secure and stable work environment for tasks conducted at heights, reducing the risk of accidents. Simultaneously, the ability to create temporary work platforms ensures that workers can efficiently access elevated areas, boosting overall productivity and expediting construction processes. Their adaptability, durability, and role in enhancing workplace safety make them a valuable asset in a wide range of industrial and construction scenarios.
Benefits of Heavy-Duty Steel Trestles
1. Exceptional Load-Bearing Capacity
Heavy-duty steel trestles have many benefits in addition to their excellent load-bearing capacity. They can withstand even the most demanding working conditions thanks to their inherent strength and tough structure, which makes them incredibly resistant to wear and tear. Their longevity is increased by their durability, which also guarantees that they can constantly satisfy the requirements of heavy-duty applications.
2. Unrivaled Corrosion Resistance
Heavy-duty steel trestles exhibit remarkable resistance to corrosion and rust, making them impervious to the detrimental effects of weather elements. This unique attribute positions them as the go-to choice for tasks in all weather conditions and outdoor projects. Moreover, their non-corrosive nature significantly reduces maintenance costs and effort, providing a cost-effective and hassle-free solution.
3. Safety and Dependability
From a safety perspective, heavy-duty steel trestles are invaluable assets. Their unwavering stability and unwavering rigidity make them reliable tools for a wide range of critical applications. These trestles are engineered to ensure the safety of workers and to provide a secure platform for various tasks, instilling confidence in their performance and safeguarding workers in demanding environments.
4. Versatile and Essential
Heavy-duty steel trestles emerge as essential and versatile tools across diverse industries. They are designed to endure the rigors of heavy-duty applications while consistently delivering commendable performance. Their relatively long lifespan, coupled with their inherent ruggedness and safety features, renders them a highly worthwhile investment for any project or industry, guaranteeing durability and reliability for the long haul.
Final Thoughts
Heavy-duty steel trestles are an all-in-one solution for all your heavy-duty load-bearing tasks. They amalgamate strength, durability and functionality, solidifying their status as invaluable assets in the realm of industrial and construction operations. Whether you run a construction, mining, or manufacturing business, understanding the benefits and uses of these trestles can contribute to streamlining your operations and reducing overhead costs. The adaptability and versatility they offer makes them worth considering for your business.
If you plan to carve a niche in the defence engineering contracting industry, knowing the top skills required for success is crucial. In this dynamic and expanding field, technical understanding meets strategic thinking. Employers and clients are increasingly demanding a holistic skill set, including exceptional technical knowledge, effective communication abilities, proficient project management, a keen eye for innovative solutions, and engineering contractor expertise.
The defence industry deals with high-stakes projects where the product delivered – be it a piece of equipment, infrastructure, or a strategic plan – can ultimately have significant national security implications. Therefore, the value of a diverse skill set in this field cannot be understated. Below are some of the most sought-after skills in defence engineering contracting.
1. Technical Proficiency
Any engineering contractor’s expertise begins with their technical capability. It is the backbone of their professional offering and forms the starting point of their value proposition. Whether it’s mechanical, electrical, civil, or any other sub-discipline of engineering, a solid foundation and extensive knowledge are crucial. This technical understanding extends to computer-based applications used in the industry, from CAD and CAM systems to project management softwares.
Advancements in technology are continually changing the landscape of defence engineering. Getting used to adopting new technical tools and updating existing skills is crucial for success. Engineers who keep learning and improving their skills will stay ahead of the curve in the contracting industry.
2. Strategic Thinking
In the realm of defence, the application of a strategic mindset to engineering projects is paramount, complementing technical prowess. Predicting potential outcomes and making well-informed decisions under high-pressure situations are skills of immeasurable importance in ensuring the success of defence initiatives. Moreover, this strategic thinking is not confined solely to the battlefield but extends into vital areas like assessing and mitigating risks, meticulously planning logistics to ensure timely deployment, and conducting astute financial analyses to optimize resource allocation. In essence, strategic thought underpins the very foundation of effective defence operations, ensuring that every facet of a mission is meticulously planned and executed to achieve its objectives while minimizing risks and maximizing efficiency.
3. Communication Skills
Effective communication stands as a cornerstone within the defence engineering contracting industry. These engineers perform a pivotal role by serving as intermediaries between builders, designers, and clients, adeptly translating intricate technical details into comprehensible terms. Beyond their technical responsibilities, they must engage in contract negotiations, skillfully manage team dynamics, and present their ideas persuasively. These multifaceted interactions demand not only exceptional communication skills but also the capacity to tailor messages precisely to suit different audiences. In essence, proficiency in communication is the linchpin that enables defence engineers to navigate the complexities of their industry successfully, facilitating collaboration, understanding, and ultimately, the successful execution of critical projects.
4. Project Management
Effective communication stands as a cornerstone within the defence engineering contracting industry. These engineers perform a pivotal role by serving as intermediaries between builders, designers, and clients, adeptly translating intricate technical details into comprehensible terms. Beyond their technical responsibilities, they must engage in contract negotiations, skillfully manage team dynamics, and present their ideas persuasively. These multifaceted interactions demand not only exceptional communication skills but also the capacity to tailor messages precisely to suit different audiences.
5. Innovation and Creativity
In the defence industry, one frequently encounters distinctive challenges that demand innovative and unconventional solutions. A defence engineering contractor’s capacity to break free from traditional paradigms and think creatively is a substantial asset in this field. By fostering a culture of out-of-the-box thinking, these professionals can uncover fresh approaches and craft novel solutions that can address the industry’s ever-evolving and unique problems. In essence, embracing creativity and innovation becomes a cornerstone for success in the defence industry, allowing contractors to adapt and respond effectively to the dynamic and complex nature of defence-related challenges.
6.The Link Between Technical Expertise and Soft Skills
There’s a prevailing misconception that the technical skills of engineers surpass their soft skills. However, the defence engineering contractor expertise sheds a different light on this. While technical proficiency is crucial, the ability to communicate effectively, manage projects, and strategize are equally important. These skills can only be cultivated through years of experience and interactive learning.
Staying ahead in the dynamic field of Defence Engineering involves constant upskilling and an openness to learn and adapt. While these skills provide a general indication of what is expected in the industry, individual job descriptions may vary. A multi-skilled approach will always put a defence engineering contractor in good stead, ensuring a successful career in this demanding but rewarding field.
Final Thoughts
The top skills for success in the defence engineering contracting industry include technical proficiency, strategic thinking, excellent communication, adept project management, and the capacity for innovation and creativity. Cultivating these qualities will prepare an individual for the challenges and opportunities in this industry, thereby paving the way for a successful career.
Eutrophication in US freshwaters costs approximately $2.2 billion per year. Astonishing, right? Want to know more about this process that can wreak havoc if left unchecked? In this blog, let’s visit a eutrophied lake and understand the entire events that lead to eutrophication and its effects.
Eutrophication is the process of excessive enrichment of nutrients in a water body, resulting in the abundant growth of algae. This process is indicated by the excessive development or bloom of algae and plankton in a water body.
Eutrophication is a severe environmental concern because it frequently leads to deterioration of water quality and dissolved oxygen depletion in the water bodies. Eutrophic waters can eventually turn into “dead zones” that can not support life.
Many lakes are naturally eutrophic, and in some situations, eutrophication progresses as the lake ages. Eutrophication is a term that is more commonly associated with human actions, such as the introduction of synthetic plant fertilisers. This has resulted in community changes and deterioration of water quality in many freshwater systems.
As the human population has grown and agriculture has expanded, the use of artificial fertilizers has become a necessity. Consequently, eutrophication now ranks with other major anthropogenic effects like deforestation, global warming and depletion of the ozone layer.
In the next section, I will show you how a water body undergoes eutrophication.
Eutrophication Process
Soil receives nutrients in excess from synthetic fertilizers. Surface runoff washes them away into the water body.
Nutrients reach the water body via untreated sewage and industrial effluents too.
Excess nutrients cause accelerated growth of algae or algal bloom.
Light penetration reduces due to the algal bloom.
Plants beneath the algal bloom perish because they are unable to perform photosynthesis in the absence of sunshine.
The algal bloom eventually dies and settles to the lake’s bottom.
Bacterial populations begin to break down the remnants, consuming oxygen in the process.
Oxygen is lost in the water as a result of decomposition.
Aquatic organisms die due to a lack of dissolved oxygen. The waterbody turns into a dead zone which doesn’t support life.
Eutrophication – Algal bloom
Types of Eutrophication
Based on the source of nutrient enrichment, there are two types of eutrophication. They are:
Natural Eutrophication
Although human activities are the most prevalent cause of eutrophication, it can also be a natural process, especially in lakes. Due to climate change, geology and other external factors, the nutrient density of a water body increases over time and undergoes the process of natural eutrophication.
A few lakes also show the reverse process called meiotrophication. In this process, nutrient-poor inputs make the lake less nutrient-rich over time. Artificial lakes and reservoirs usually undergo this process, which starts out as very eutrophic but eventually become oligotrophic. An oligotrophic lake is a lake with low primary productivity due to low nutrient content.
The major difference between natural and anthropogenic eutrophication lies in the timescale. The former takes geologic ages to complete while the latter is a quick process.
Cultural Eutrophication
Eutrophication caused by human activity is also known as cultural or anthropogenic eutrophication. It is a process that accelerates natural eutrophication. Land runoff increases as a result of the land clearing and construction of towns and cities. Therefore, surface runoff from croplands carry nutrients such as phosphates and nitrate into the lakes and rivers, and then to coastal estuaries and bays.
When excess nutrients from anthropogenic sources such as runoff from fertilised croplands, lawns, and golf courses, untreated sewage and wastewater end up in water bodies, they cause nutrient pollution and simultaneously speeds up the natural process of eutrophication. The degradation of water quality induced by cultural eutrophication severely impacts human uses such as potable water, industrial usage, and recreation.
Let’s move on to the section describing its effects or consequences.
Eutrophication Effects
The effects of eutrophication range from ecological losses to economical losses. Let’s have a closer look at each one of them.
Loss of Biodiversity
Aquatic environments support a diverse range of plant and animal life, both primitive and complex. The process of eutrophication disrupts the ecosystem’s balance by promoting the growth of basic plant life. The ecosystem’s biodiversity is drastically reduced as a result of the loss of some desirable species.
The most noticeable consequence of cultural eutrophication is the formation of dense blooms of toxic, foul-smelling blue-green algae or cyanobacteria that impairs water clarity and quality. Algal blooms reduce light penetration. This limits aquatic plant growth and diminishes the success of predators that rely on light to hunt and catch prey in the benthic zone. Eventually, it leads to the mass death of aquatic plants and organisms.
Furthermore, eutrophication’s high rates of photosynthesis drain dissolved inorganic carbon and elevate pH to dangerously high levels throughout the day. By diminishing chemosensory skills, elevated pH can ‘blind’ organisms that use the sense of dissolved chemical cues for survival.
When the dense algal blooms die, microbial breakdown depletes dissolved oxygen, resulting in a hypoxic or anoxic “dead zone” where most species are unable to survive. Many freshwater lakes contain dead zones. Eutrophication-induced hypoxia (extremely low oxygen concentrations in bottom waters) and anoxia pose a danger to profitable commercial and recreational fisheries around the world.
Eutrophication – Blue Green Algae
Harmful Algal Blooms (HABs)
Some algal blooms are also dangerous because they produce toxins like microcystin and anatoxin-a. Harmful algal blooms (HABs) leads to:
water quality degradation
the extinction of commercially important fishes
public health problems
Toxic cyanobacteria such as Anabaena, Cylindrospermopsis, Microcystis, and Oscillatoria (Planktothrix) dominate nutrient-rich, freshwater systems due to their superior competitive abilities under high nutrient concentrations, low nitrogen-to-phosphorus ratios, low light levels, reduced mixing, and high temperatures.
Toxic cyanobacteria bloom causes poisonings of domestic animals, wildlife, and even humans all around the world. For instance, shellfish poisoning is a result of HABs. Shellfish ingests the biotoxins produced during algal blooms. When humans consume them, it leads to various kinds of poisoning including paralytic, neurotoxic, and diarrhoetic shellfish poisoning.
Ciguatera, a predator fish becomes a vector for such toxins by accumulating the poison in its body and then poisoning the humans who consume it. Furthermore, cyanobacteria are responsible for various off-flavour compounds (such as methyl isoborneol and geosmin) detected in municipal drinking water systems.
Monetary Loss
Due to the continuous feeding of the fish, aquaculture ponds often accumulate high concentrations of nutrients such as nitrogen and phosphorus. As a result, these ponds are subjected to cyanobacterial blooms and hypoxia regularly. aquaculture-reared fish, resulting in significant financial losses.
Eutrophication also lowers the recreational value of rivers, lakes, and beaches. This severely impacts the tourism sector. When eutrophic conditions interfere with the treatment of drinking water, health concerns and monetary losses arise.
OK, I know what you’re thinking. How to control eutrophication, right? Read on to find more.
Eutrophication Control Measures
Prevent the flow of plant nutrients to water bodies. Reduce the overuse of synthetic fertilizers.
Proper channelling of agricultural wastes and runoffs.
Releasing only safe and treated effluents to water bodies.
Seaweed cultivation absorbs nitrogen and phosphorous and removes excess nutrients.
Promoting the growth of shellfish.
That’s it about eutrophication. Hope you found it useful.
Water pollution has become a pressing problem all over the globe. In the previous blog, we had a look at the major water pollutants. In this blog, let me walk you through the effects and causes of water pollution.
All water bodies have an innate ability to cleanse themselves. They can easily handle small volumes of pollutants and degrade them with the help of dissolved oxygen and the microbial population residing there. However, every day, 2 million tons of sewage, industrial, and agricultural waste reaches water bodies all over the world.
Together these wastes exert a huge Biochemical Oxygen Demand. The dissolved oxygen in water becomes insufficient to meet the BOD requirements. In such a situation, when oxygen demand exceeds oxygen availability the water body becomes polluted.
Causes of water pollution
Water being the ‘ Universal Solvent ‘ dissolves a wide range of substances easily. Therefore any unwanted substance that reaches a water body easily mixes with the water and pollutes it. The causes of water pollution can be natural and anthropogenic. The natural causes of water pollution include oil spills from sedimentary rocks in the seabed, storms, natural eutrophication etc. However, these contribute only to a very small percentage of the pollution load.
The major cause of water pollution is the release of sewage and industrial effluents into water bodies without treating them. These effluents introduce a variety of water pollutants like inorganic chemicals, plant nutrients, detergents, oil, pathogens, etc to the water bodies. Please visit our blog, What are Water Pollutants for complete information about all the water pollutants.
Now, let’s look at the effects of water pollution.
Water Pollution Effects
Water pollution affects humans and the organisms thriving in and around the water body. This includes the benthic, aquatic and semi-aquatic organisms and also their predators. Let’s look at the effects of water pollution on the environment in the first section.
Eutrophication
The enrichment of a water body by plant nutrients such as phosphorous and nitrogen is eutrophication.
The surface runoff from agricultural lands and untreated industrial effluents carry large volumes of these plant nutrients into rivers and lakes.
This accelerates the growth of algae.
The algal bloom eventually dies and settles to the lake’s bottom.
Bacterial populations begin to break down the remnants, consuming oxygen in the process.
Further, the lake turns into a dead zone supporting no life.
One of the unseen effects of water pollution is the disruption of food chain. When organisms in a particular trophic level accumulates toxins due to water pollutants, their predators in the next trophic level get poisoned and may die. The number of predators comes down drastically. This in turn has consequences on organisms in both the succeeding and preceding trophic levels.
Let me make it clear with an example. During eutrophication, the aquatic plants die off since they can’t perform photosynthesis. As a result, small fishes which feed on these plants experience a food shortage. Slowly, their population also starts to decline.
The same process repeats in higher trophic levels too. The consequences are so far-reaching that it affects not only aquatic organisms but also piscivorous birds. Thus the accumulation of pollutants in a water body can disrupt the entire food chain in and around it.
As per the statistics from the Centre for Biological Diversity on the effects of the Deep Horizon spill, the 2010 spill on the Gulf of Mexico harmed over 82,000 birds, 25,900 marine animals, 6165 sea turtles, and an unknown number of fish and invertebrates.
Along with eutrophication, oil spills are a major cause of the massive death of organisms. Vast expanses of oil spills trap the seabirds and prevent them from flying away. Thus, they die either due to drowning or by their predators like sharks. Even if the birds manage to escape from the oil spill, oil destroys the water repellence of its feathers.
Birds and mammals die from hypothermia when they lose the ability to repel water and insulate from the cold water. Also, marine organisms and birds may die due to oil poisoning as they tend to ingest oil while cleaning themselves.
Water Pollution – Death of Marine Species
Economic Effects of Water Pollution
It is costly to manage and restore polluted water bodies. For example, following the Fukushima tragedy, Japan announced in 2019 that it is running out of space to retain the polluted water. Over a million tonnes of contaminated water are currently kept in tanks. According to estimates, cleaning up the disaster’s aftermath will cost at least $660 billion.
Purifying drinking water costs more under normal circumstances, not to include the health costs of treating diseases caused by contaminated water. Eutrophication in US freshwaters costs approximately $2.2 billion per year.
Loss of Aesthetic Value
Winds and currents carry the oil spills into the shore. Oil forms a thick layer over the beaches and rocks. Thus it reduces the aesthetic value of beaches and is a big threat to tourism and recreation on beaches. Moreover, polluted water bodies develop foul odours and unpleasant colours both of which destroys their aesthetic beauty and reduces human interaction.
Biomagnification refers to the progressive increase in the concentration of toxins from organisms of one trophic level to the next.
As a result, organisms in the higher trophic level which may not have direct exposure to water pollutants are also harmed.
For instance, predatory birds like vultures and eagles accumulate dieldrin, DDT in their bodies by consuming fish poisoned with pesticides.
When these pesticides reach their body, the concentrations are high enough to impact them severely. Dieldrin affects the calcium metabolism in predatory birds and leads to thinning of their eggshells.
The worst-hit are always the ones in the highest trophic level, which in most cases are human beings. Diseases like itai-itai and Minamata disease remain painful reminders of the effects of biomagnification and water pollution. In the next section, let’s have a closer look at the effects of water pollution on human health.
Water Pollution Effects on Human Health
Water acts as a carrier of many harmful pathogens which causes water-borne diseases in human beings. Since contaminated water is the primary mode of transmission for these diseases, they are known as water-borne diseases.
The majority of intestinal (enteric) disorders are contagious and spread by faeces. Pathogens are disease-causing agents found in the faeces of infected people. They include viruses, bacteria, protozoa, and parasitic worms. These infections spread through water sources and directly infect people who handle food and water. Let me show you a few of those diseases:
Bacterial diseases
Vibrio Cholerae is responsible for diarrhoea, the most common water-borne disease. This bacterium releases toxins in the digestive tract and leads to watery bowel movements, dehydration and renal failure. According to WHO, diarrhoea kills around 525000 children below 5 years, every year.
Shigella bacteria cause Shigellosis that affects the digestive tract of humans and damages the intestinal lining. Salmonella bacteria are found in contaminated water and it causes fatal salmonellosis that results in inflammation of the intestine and death.
Bacterial diseases
Viral Diseases
Firstly, drinking contaminated water causes Hepatitis, a viral disease that infects the liver. Secondly, contaminated water also becomes a breeding ground for mosquitoes that spread Encephalitis. Poliomyelitis virus is responsible for poliomyelitis and spreads through contaminated water.
Parasitic Diseases
Parasitic diseases transmitted via contaminated water includes Cryptosporidiosis by cryptosporidium parvum, Galloping amoeba by the Entamoeba histolytica and Giardiasis by Giardia lamblia.
Now, let me show you the health effects of some particular water pollutants.
Pesticides – carbonates and organophosphates present in them damage the nervous system and cause cancer. Chlorides can cause reproductive and endocrinal damage.
Nitrates – especially affect babies that drink formula milk. It reduces the amount of oxygen in the blood and causes the “blue baby” syndrome.
Arsenic – causes liver damage, skin cancer and vascular diseases
Fluorides – in excessive amounts makes the teeth yellow and causes spinal cord damage.
Water is a natural resource that all living things require for survival. Any reckless behaviour on the part of humanity has an impact on all other organisms. As a result, water bodies must be protected from pollution.
Constructed wetlands are wastewater treatment systems that utilise natural processes such as plants, soil, and organisms to treat wastewater, greywater, or stormwater runoff from municipal or industrial sources. In this blog, let’s go for a trip exploring the different types of constructed wetlands and their mechanism.
Let’s get started by understanding the basics of a constructed wetland.
Constructed wetlands are manmade wetlands that find applications in land reclamation after mining and compensating for natural areas lost to development. They operate as a biofilter and remove a variety of pollutants from the water such as organic substances, fertilisers, pathogens, and heavy metals. It can also eradicate pathogens (bacteria, viruses, protozoa, and helminths) to a certain extent.
Constructed Wetlands Components
There are three main components in constructed wetlands:
An impermeable layer of Clay
A Substrate layer of gravel
Ground Vegetation Zone
The impermeable layer, which is often comprised of clay, inhibits pollutants from filtering into the lower aquifers. It is the bottom-most layer.
Above the impermeable layer lies the substrate layer. that nourishes and protects the root zone. The water passes through this layer and into the root zone. Bioremediation and denitrification take place in this layer with the help of bacteria present in the roots. The ground vegetative layer rests above the substrate layer.
Constructed wet lands
In a wetland, vegetation offers a substrate (roots, stems, and leaves) for microbes to proliferate as they decompose organic matter. This microbial colony or the periphyton accomplishes around 90% of pollution removal and waste decomposition. When the plants degrade, they provide a carbon source for the microorganisms and eliminate roughly 7% to 10% of contaminants.
As wastewater flows through the wetland medium and the plant rhizomes, it undergoes treatment through various physical, chemical and biological processes.
The oxygen which comes out of the rhizomes, roots, and rootlets, forms a thin layer surrounding each root hair.
This creates aerobic conditions for the aerobes to act. Along with the aerobic bacteria, anaerobic bacteria also acts on the wastewater.
Microbial nitrification and subsequent denitrification releases nitrogen gas. In the root-bed media, phosphorus coprecipitates with iron, aluminium, and calcium compounds.
Filtration and adsorption by biofilms on the gravel or sand media reduces the harmful bacteria and viruses.
Nitrogen Removal
Ammonia present in the wastewater converts to ammonium ions. The aerobic bacterium Nitrosomonas sp. oxidizes these ammonium ions to nitrite. Nitrite converts to nitrate by the action of the the bacterium Nitrobacter sp. Finally, nitrate reduces to relatively harmless nitrogen gas under anaerobic conditions. It then enters the atmosphere.
Phosphorus Removal
Phosphorus removal and storage occurs within the constructed wetland itself since the phosphorus cycle is closed and there is no release of it into the atmosphere. A wetland system sequesters phosphorus by:
Incorporating phosphorus into living biomass and thereby becoming a part of the organic matter present in living beings.
Precipitation of phosphorus as insoluble phosphates with ferric iron, calcium, and aluminium compounds found in wetland soil.
Constructed Wetlands Types
The following are the three primary types of built wetlands:
Subsurface flow constructed wetland
Surface flow constructed wetland
Floating treatment wetland
Let’s have a closer look at each one of them.
Subsurface Flow Wetlands
There is no water surfacing in subsurface flow constructed wetlands because wastewater flows through the roots of the plants which lies below the gravel. As a result, these types of constructed wetlands offer the following advantages:
The system is more efficient
Attract fewer mosquitoes and flies.
Emit less stink.
Less susceptible to cold temperatures.
Water purification takes up lesser space.
There are two types of subsurface flow constructed wetlands: Horizontal flow and vertical flow constructed wetlands
Horizontal Flow Constructed Wetlands
The effluent in the horizontal flow built wetland moves horizontally and parallel to the surface. Absence of surface water, preventing mosquito breeding. Subsurface flow wetlands can treat a variety of different wastewaters, such as household wastewater, agricultural, paper mill wastewater, mining runoff, tannery or meat processing wastes, stormwater.
Vertical Flow Constructed Wetlands
A vertical flow constructed wetland is a planted filter bed with a bottom drain. A mechanical dosing system pours or doses wastewater onto the surface from above. Water runs down vertically through the substrate layer to the basin’s bottom, where it is collected in a drainage pipe. In comparison to horizontal flow constructed wetlands, vertical flow constructed wetlands are more efficient and use less space.
Surface flow wetlands resemble wastewater treatment ponds in appearance such as “waste stabilisation ponds”. They find applications in tertiary treatment, wastewater treatment plant effluent polishing and stormwater runoff treatment
Along with natural decay, predation by higher species, pathogens die by UV radiation due to the exposure of water to direct sunlight, . The soil layer beneath the water is anaerobic, but the roots of the plants produce oxygen, allowing complex biological and chemical interactions to take place.
A wide range of soil types, including bay mud and various silty clays, can support surface flow wetlands.Plants like Water Hyacinth (Eichhornia crassipes) and Pontederia spp. are employed.
Constructed Wetlands
Surface flow constructed wetlands, on the other hand, may increase mosquito breeding.
They also produce a lot of algae, which degrades the effluent quality.
In comparison to subsurface flow built wetlands, they require a larger area to cleanse water.
They have a stronger odour and lesser performance in the winter.
Floating treatment wetlands
The floating treatment wetlands (FTWs) are artificial wetlands that replicate natural ones. Floating rafts support hydroponically grown plants in FTWs. The rafts float on the surface of a wet pond and they improve water quality by filtering, consuming, or breaking down contaminants (such as nutrients, silt, and metals) in the water.
Shall we wrap up?
Conclusion
Due to the self-sustaining nature of the constructed wetlands they have a significantly lower lifetime costs compared to the conventional treatment systems. Hence they provide an economical and nature-friendly option for wastewater treatment.
So, how was the trip? Let us know in the comments.
Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) are widely used analysis methods in water treatment plants, petrochemicals and drinking water treatment. In this blog, let me walk you through the analysis of Chemical Oxygen Demand, Total Organic Carbon and its applications.
Chemical Oxygen Demand is the amount of oxygen required to oxidise all the biodegradable and non-biodegradable organic matter. It evaluates all chemically oxidizable components present in a given wastewater sample. It can be directly linked to the effluent’s actual oxygen requirement on releasing into the environment. Total Organic Carbon testing, in addition to Chemical Oxygen Demand, provides us with a better understanding of a waste stream’s true organic load.
Why COD and TOC are important
COD (Chemical Oxygen Demand) and TOC (Total Organic Carbon) analysis play a vital role in keeping our waterways safe and healthy. By measuring the levels of organic pollution in water and wastewater, these tests help us monitor water quality, evaluate the efficiency of treatment processes, and ensure that we’re meeting environmental regulations. Ultimately, they safeguard our well-being and the delicate balance of aquatic ecosystems.
Significance of COD/TOC Ratio
The COD/TOC ratio is a useful tool for assessing the biotreatability of wastewater treatment.
At a given point in the wastewater treatment process, the ratio of COD to TOC provides insight into the nature of organic wastewater constituents present.
A high COD/TOC ratio indicates easily oxidisable organic molecules like alcohols.
Ratios in the range of 0.8 or higher indicate wastes with a high biochemical treatment potential.
Lower ratios indicate that the wastes are not amenable to biochemical treatment.
The amount of oxygen required as measured by the COD value may change during wastewater treatment, but the carbon concentration as measured by the TOC value does not.
As the COD/TOC ratio of wastewater decreases during treatment, it means that the organic compounds are undergoing oxidation and the treatment plant is functioning smoothly.
The COD determination is similar to the BOD determination in the fact that both methods use titration. The basic principle of the COD test is that a strong oxidizing agent can fully oxidize almost all organic compounds to carbon dioxide under acidic conditions.
The best choice would be potassium dichromate which is a strong oxidizing agent under acidic conditions. The addition of sulfuric acid creates acidic conditions for titration. Usually, we use a 0.25 N solution of potassium dichromate for COD determination. However, for samples of COD below 50 mg/L, we use a lower concentration of potassium dichromate.
During the oxidation of the organic substances found in the water sample, potassium dichromate undergoes reduction and forms Cr3+. After the completion of the oxidation reaction, the amount of Cr3+ gives an indirect measure of the organic contents in the water sample.
Procedure for Chemical Oxygen Demand
Pipette out 50 ml of the wastewater sample into a flat bottom Erlenmeyer flask.
Gently add HgSO4 and 5 mL of sulfuric acid. Swirl the flask continuously until all the mercuric sulfate has dissolved.
Now, add 25.0 mL of 0.25N potassium dichromate.
Carefully add 70 mL of previously prepared sulfuric acid-silver sulfate solution and gently swirl until the solution is thoroughly mixed.
Add glass beads to the refluxing mixture to prevent bumping.
Heat the mixture under total reflux conditions for 2 hours.
Cool down the mixture to room temperature and titrate it with standard ferrous ammonium sulfate along with 10 drops of ferroin indicator.
The end-point of titration is a sharp colour change from blue-green to reddish-brown.
Run a blank, with 50 mL of distilled water in place of the sample along with all reagents and subsequent treatment.
COD in mg/l = [(A-B)*M*8000]/sample volume in ml
A = Volume (ml) of Ferrous Ammonium Sulphate used for blank.
B = Volume (ml) of Ferrous Ammonium Sulphate used for sample
M = Molarity of Ferrous Ammponium Sulphate
8000 = milliequivalent weight of oxygen * 1000 ml/L
The COD test doesn’t differentiate between biodegradable and non-biodegradable organic materials. It gives a measure of total oxidisable organic materials in the sample. Therefore, we get higher values of COD than BOD for the same sample. Dichromate oxidises the chlorides and nitrites present in the sample. They create an inorganic COD and generates error in the COD determination.
Chemical Oxygen Demand Analysis
Chemical Oxygen Demand Testing Advantages
COD is ideal for checking treatment plant performance and water quality regularly.
In comparison to the 5-day BOD test, COD testing is more accurate and has a shorter analysis period (2-hour digesting time).
Toxic elements in the sample do not affect the COD oxidant.
Changes in COD between influent and effluent may be correlated with BOD content and can be used to augment BOD data.
Chemical Oxygen Demand Testing Limitations
The COD technique does not completely oxidise some organic molecules.
Chloride ions might cause interference in COD measurements.
Now you got a clear idea about COD determination. Let’s move on to Total Organic Carbon Analysis.
Total Organic Carbon (TOC)
Total Organic Carbon refers to the total amount of organic carbon (including elemental carbon) bound to dissolved or suspended organic substances in water. It is a non-specific indicator of water quality or cleanliness of pharmaceutical manufacturing equipment.
What does TOC Analyse?
The basic principle behind the Total Organic Carbon test is the oxidation of the carbon in the organic matter to carbon dioxide. After that, a non-dispersive infrared analyzer measures the amount of CO2. The amount of CO2 evolved gives a measure of the carbon content in the sample. Further stoichiometric calculations based on the method employed gives the amount of TOC.
TOC analysis measures the following:
Total carbon (TC)
Inorganic carbon (IC)
Total organic carbon (TOC)
Purgeable organic carbon (POC)
Nonpurgeable organic carbon (NPOC)
TOC analysis measures Total Carbon and Inorganic Carbon. Then we subtract the Inorganic Carbon (IC) from Total Carbon (TC) to find the Total Organic Carbon. This is the TC-IC method.
TOC Analysis
According to the TC-TIC method, TOC = TC -T IC
TIC-NPOC method employs acidification of the sample to evolve carbon dioxide. It gives the measure of inorganic carbon (IC) and then oxidation of sample and measurement of the remaining non-purgeable organic carbon (NPOC).
Oxidation Methods
We have a variety of oxidation and detection methods to find out the TOC. Let me show a few of them:
High-temperature combustion at 1,200 °C in an oxygen-rich atmosphere. The CO2 passes through scrubber tubes to remove interferences. After that, non-dispersive infrared absorption (NDIR) gives the amount of CO2.
High-temperature catalytic oxidation at 680 °C in an oxygen-rich environment inside tubes filled with a platinum catalyst and then NDIR.
Thermochemical oxidation in the presence of heat and a chemical oxidizer, usually a persulphate.
Photochemical oxidation in the presence of UV and a chemical oxidizer like persulphate.
Photo-oxidation by ultra-violet (UV) light alone or with a catalyst. In a UV-irradiated chamber, combine sample with persulfate to convert organics to carbon dioxide. The UV oxidation method offers the most reliable, low maintenance method of determining TOC in ultra-pure waters.
Accurate detection and quantification are very crucial to get accurate results in TOC analysis. The most commonly used methods include conductivity and non-dispersive infrared (NDIR).
TOC Applications
In oil exploration, the initial chemical study on a prospective petroleum source rock is TOC.
TOC helps in detecting pollutants in drinking water, cooling water, semiconductor production water, and pharmaceutical-grade water.
It finds applications in controlling the release of organic chemicals into the environment at a production facility.
Furthermore, a low TOC can demonstrate the absence of potentially dangerous organic compounds in pharmaceutical manufacturing water.
Because of the byproducts, TOC is also of importance in the field of drinking water treatment.
That’s it about the analysis of Chemical Oxygen Demand and Total Organic Carbon. Hope you found it informative. Let us know your queries in the comments section.
Structural steel fabrication is a process that involves bending, cutting, shaping and assembling structural steel components to create complicated and accurate industrial and residential structures. Structural steel fabrication has a very high strength-to-weight ratio. Because of this versatility and flexibility, engineers use structural steel fabrication extensively in various industrial, residential and commercial projects.
In this blog, let me walk you through the Advantages, Processes and applications of structural steel fabrication works. Here we go.
Structural steel fabrication – Stages and procedures
Structural steel fabrication involves multiple stages and requires highly skilled manpower. The training of manpower is essential for transforming raw materials into precise engineering structures. In the following sections, I will show you the processes involved in structural steel fabrication works and the involvement in crafting the structures.
Ideation and shop drawings/fabrication drawings
In the first stage of structural steel fabrication works the major processes involve ideating, blueprinting, and creating shop drawings. During this phase, the team conceptualizes the design and prepares detailed plans and drawings. We use software to create blueprint drawings, taking into account requirements, code compliances, and specifications. Blueprints and shop drawings ensure proper design and accurate pieces of information like dimensions, connections, and other specifications required for fabricating the structure.
Accurate and precise ideation, blueprints and shop drawings are the most important factors that exhibit the quality and speed of any structural fabrication work.
structural steel fabrication
Material preparation for structural fabrication
The preparation of raw steel for structural fabrication involves the following stages:
a) Material selection and inspection
b) Cutting, bending, drilling
Material selection and inspection
We perform the material selection on the basis of project requirements and specifications. Generally, this step includes the selection of the appropriate grade of material and requisite raw material quality checks before using it for work.
Cutting, bending and drilling of steel
The cutting stage encompasses the precise cutting of raw material into accurate sizes as per the shop drawings. Mostly, cutting is done with the help of various techniques. This includes sawing, which involves using a saw blade, shearing, which uses specialized machinery to make straight cuts and advanced techniques like plasma or laser cutting or water jets. Generally, these processes take place in a fabrication shop/factory. However, the shearing process is limited to small and miscellaneous structural members.
During the bending stage, the structural steel undergoes deformation to the required shape and angles. We mainly employ rolling machines or press breaks in this process. Generally, there are five common methods of bending structural steel. This includes rolling, incremental bending, hot bending, rotary-draw bending, and induction bending. Fabrication of curved or angled structures requires bending.
drilling of structural steel
Drilling of structural steel provides precise holes in structural members. This is generally done with the help of drill presses or specialized drilling machines. Drilling is basically done for bolted components.
Welding of structural steel
Welding is the process of creating a variety of welds for joining structural steel components using heat and pressure to produce continuous joints. Mostly, the welding process follows different stages:
The welding process starts with cleaning the surface and ensuring that any dirt and other impurities are not there. The next process is the fit where we assemble and align the steel sections as per shop drawings. Basically, this ensures an accurate fit-up for welding. On completion of the fit-up, we start the structural welding process.
Structural welding is done in any of the two methods. The heat from an electric arc, laser, or other welding methods is applied to melt the steel edges, forming a molten pool. Filler Material such as welding wire or rod, is added to the molten pool to strengthen the weld. The molten pool cools, solidifies, and forms a continuous bond between the steel components.
Common types of welding used in structural steel fabrication include:
Engraving in structural steel fabrication involves etching or inscribing markings, identification codes, or specific details onto the steel components. Specialized engraving tools or laser engraving machines perform this step.
Assembly is the final stage where we combine the fabricated steel components, often through welding, bolting, or riveting, to create the completed structure. These steps ensure proper identification, alignment, and secure connections, contributing to the structural integrity and functionality of the steel assembly.
Conveying for erection
The fabricated members are conveyed to the area of erection where these members are erected and aligned according to the drawings.
Advantages of structural steel fabrication
Structural steel fabrication offers a wide variety of advantages,
High Strength and Durability: Structural steel possesses excellent strength-to-weight ratio and durability, providing long-lasting and resilient structures.
Design Flexibility: Steel fabrication allows for versatile and customizable designs, accommodating complex architectural and engineering requirements.
Fast Construction: Prefabrication of Steel components enables efficient and speedy on-site assembly, reducing construction time and costs.
Structural Integrity: Steel’s inherent properties ensure structural integrity, capable of withstanding heavy loads, seismic forces, and extreme weather conditions.
Sustainability: Steel is recyclable and reusable, reducing environmental impact and promoting sustainability in construction projects.
Cost-Effective: Steel fabrication offers cost efficiencies due to faster construction, reduced labor requirements, and minimized maintenance needs.
Precision and Quality: Since steel fabrication takes place under controlled conditions, it ensures high precision, quality, and dimensional accuracy.
Fire Resistance: Steel is non-combustible and can withstand high temperatures, enhancing fire resistance and safety.
Adaptability: Generally, steel structures give the option for easy modification, expansion, or retrofitting to accommodate future changes or renovations.
Aesthetic Appeal: Steel’s sleek and modern appearance provides architectural versatility and visually appealing structures.
These advantages contribute to structural steel fabrication’s widespread use and popularity in various construction projects.
Applications of structural steel
Structural fabricated construction mainly has the following applications
High-rise buildings
Industrial Buildings
Residential Buildings
Parking Garages and multilevel parking
Bridges
Shall we wrap up?
Conclusion
In this blog, we saw the advantages, processes and applications of structural steel fabrication works. I hope you found it insightful. In case of any queries, please feel free to ask in the comments.
Fiber-reinforced concrete (FRC), an advanced form of Reinforced Cement Concrete is finding wide applications these days. Fiber-reinforced concrete (FRC) is a versatile and durable composite material consisting of a cementitious matrix with uniformly dispersed fibers. The addition of discontinuous, discrete fibers to cement, mortar or concrete mixes can enhance the concrete properties. Ever thought why do we add different kinds of fibres to the Reinforced Cement Concrete and what are the different types of fibres that we add? Stay with me till the end of this blog and we will find answers to all these questions.
First, let’s have a look at the basics of fiber-reinforced concrete and its applications.
What is Fiber-reinforced concrete?
Fiber-reinforced concrete (FRC) is a versatile and durable composite material consisting of a cementitious matrix with uniformly dispersed fibers. The addition of discontinuous, discrete fibers to cement, mortar or concrete mixes can enhance the concrete properties. These fibers act as reinforcement throughout the concrete matrix, and control cracking due to plastic shrinkage and drying shrinkage. Fiber-reinforced concrete reduces the permeability of concrete and reduces water bleeding.
Fiber reinforced concrete finds extensive applications in various infrastructure works, industrial flooring works and other construction works that demand enhanced durability and crack control. FRC improves the flexural and impact resistance and hence we prefer it for structures subjected to dynamic or heavy loads.
Now, let’s discuss the reason behind the addition of fibres to the reinforced concrete.
Principle of Fiber-reinforced concrete
Fibre-reinforced concrete uses discrete fibres to improve its mechanical properties, making it stronger, more durable, and resistant to cracking. Fiber is a small piece of circular or flat reinforcing material possessing certain characteristics and properties. These fibers are of steel, glass, synthetic polymer fibers and natural fibers like jute or hemp.
Fibers are available in various sizes ranges from a few millimeters to a few centimetres. They are uniformly distributed throughout the concrete matrix. The features of Fiber reinforced concrete depends on the character and percentage, diameter and length of fibers and water-cement ratios. Typically fiber reinforced concrete is used in shotcrete but can also be used in normal concrete.
The addition of fibres to concrete controls the shrinkage cracking, lower permeability, and reduce water bleeding. Some fibers enhance impact, abrasion, and shatter resistance. However, they do not increase flexural strength or replace structural steel reinforcement.
We measure the amount of fiber as a percentage of total volume (Vf) and typically ranges from 0.1 to 3%. Aspect ratio (l/d) affects strength and toughness, but long fibers can hinder workability. Recent research shows limited impact resistance improvement, with microfibers performing better than longer fibers.
Types of Fiber-reinforced concrete
The type of fiber-reinforced concrete depends on the nature of the structure and applications. Let us have a look at the most common types of fibre reinforced concretes commonly used in construction.
SFRC is a composite material that includes a certain amount of steel fibers in the concrete mix. These fibres can change the properties of concrete and thereby enhance the performance of concrete. The typical diameter lies in the range of 0.25 to 0.75mm. Steel fibers having a rectangular c/s are produced by silting the sheets about 0.25mm thick.
SFRC offers numerous advantages, including improved tensile strength, crack resistance, impact resistance, and durability. The steel fibers act as reinforcement, effectively bridging cracks and enhancing the concrete’s structural integrity. The steel fiber types are as per ASTM A.820 Type I: cold-drawn wire, Type II; cut sheet, Type III: melt-extracted, Type IV: mill cut and Type V: modified cold-drawn wire.
SFRC finds applications in industrial floors, pavements, tunnels, and precast elements, where increased toughness and load-bearing capacity are required. It is also widely used in applications prone to dynamic loading, such as blast-resistant structures and earthquake-resistant buildings.
Glass fiber-reinforced concrete
Glass Fiber Reinforced Concrete (GFRC) is a composite material incorporating fine glass fibers into the concrete mix. These fibers, typically around 3-12 mm in length, enhance the concrete’s strength, durability, and flexibility. GFRC is commonly used in architectural applications, such as cladding, facades, and decorative elements, due to its lightweight nature and ability to create intricate designs.
Polypropylene Fiber Reinforced Concrete (PFRC) is a composite material that combines polypropylene fibers with concrete. One of the cheapest & abundantly available synthetic fiber/ polymer is polypropylene. They are resistant to most chemicals and only the cementitious matrix will deteriorate first. These discrete fibers, typically ranging from 6 to 30 mm in length uniformly dispersed in concrete will control cracking due to plastic and drying shrinkage.
We usually use these fibers in concrete to control cracking due to plastic shrinkage and drying shrinkage. The fibers act as reinforcement and reduce the permeability of concrete and thus reducing the bleeding of water and improving crack resistance, impact resistance, and durability. Polypropylene fibers being hydrophobic can be easily mixed as they do not need lengthy contact during mixing and only need to be evenly distressed in the mix.
Polyester fiber reinforced concrete
Polyester fiber-reinforced concrete is a composite material that incorporates polyester fibers into the concrete mix. These fibers, typically short and discrete, improve the concrete’s toughness, crack resistance, and impact resistance. Polyester fibers due to the high tensile strength and resistance to alkalis make them suitable for various construction applications that demand enhanced durability.
Carbon fibers
Carbon fiber reinforced concrete (CFRC) is a composite material that combines concrete with carbon fibers about 5-10 microns in diameter having carbon atoms. The carbon fibers, known for their exceptional tensile strength and stiffness, low weight, high chemical resistance, high-temperature tolerance and low thermal expansion impart their qualities to the concrete.
We manufacture carbon fibers by baking plastic resins. They have high strength-to-weight ratio. Carbon fibers form the most recent and probably the most spectacular addition to the range of fiber available for commercial use. Since they are more vulnerable to damage than even glass fiber, we generally treat them with resin coating.
Macro synthetic fibers
Macro synthetic fibers are synthetic fibers used as reinforcement in concrete. These fibers, typically longer and thicker than traditional fibers, are manufactured from a blend of polymers. These fibers are developed for shot create or sprayed concrete. But they find extensive applications in floor slabs for enhancing the concrete’s toughness, crack resistance, and impact resistance.
They offer improved durability and control of plastic shrinkage cracking. This makes them suitable for various construction applications in marine and coastal structures which require enhanced performance and reduced maintenance.
Advantages of fibre-reinforced concrete
Enhanced Durability: FRC increases the impact, fatigue, and abrasion resistance of concrete structures while minimising cracking. It increases the tensile strength and durability of the concrete.
Crack prevention: The use of fibres reduces the spread and enlargement of cracks by controlling plastic and drying shrinkage cracking.
Permeability Reduction: Fibres make concrete less permeable, which reduces water bleeding and improves resistance to moisture infiltration.It reduces the air voids and water voids and the inherent porosity of gel.
Improved Impact Resistance: Certain types of fibres enhance the impact resistance of concrete, making it more resilient against sudden loads and external forces.
Increased Toughness: The bridging action of the fibres, which absorbs energy and prevents abrupt failure, gives FRC an improved level of toughness.
Design Flexibility: Using fibres in concrete allows for design flexibility, enabling the creation of complicated shapes and architectural freedom.
Simplicity: Using fibre reinforcement instead of or less frequently than standard steel reinforcement simplifies construction operations.
Better Workability: Fibres can make concrete mixes more workable and cohesive, making placement and compaction easier.
Corrosion Resistance: In some circumstances, fibre reinforcement can reduce the likelihood that concrete buildings will corrode.
Sustainable: Fibre-reinforced concrete is a sustainable solution since it can increase the longevity of structures and lessen the reliance on non-renewable resources.
Creep Resistance: Fibres such as graphite and glass have excellent resistance to creep, while the same is not true for most resins. Therefore, the orientation and volume of fibres have a significant influence on the creep performance of rebars/tendons.
Shall we wrap up?
Conclusion
In this blog, we saw the properties, uses, types and advantages of fiber-reinforced concrete. If you have any queries please feel free to ask in the comments.
Terrazzo flooring is a stunning and durable option for residential and commercial spaces. It combines marble, quartz, granite, or glass chips with a cement or epoxy binder to create a unique and elegant surface. Terrazzo floors offer endless design possibilities, with various colours, patterns, and finishes available. With its timeless appeal, durability, and low maintenance, terrazzo flooring is a popular choice for those seeking a beautiful, long-lasting solution.
Terrazzo flooring incorporates a mix of materials such as marble, quartz, granite, or glass chips, creating a visually striking and versatile floor. Its popularity stems from its exceptional durability, easy maintenance, and ability to be customized to suit any aesthetic, making it a preferred choice for architects and designers.
Terrazzo flooring comes in various types, each offering unique characteristics and aesthetic appeal. From traditional and Venetian to epoxy and rustic, here are some common terrazzo flooring types to explore.
Traditional Terrazzo: This type uses a cement binder mixed with marble, quartz, or other aggregates. They provide a classic and timeless look.
Epoxy Terrazzo: Instead of cement, epoxy resin is used as the binder. Epoxy terrazzo offers greater design flexibility, durability, and a smoother finish.
Venetian Terrazzo: Originating from Italy, Venetian Terrazzo features a polished finish and intricate patterns. These patterns are created by embedding various colourful marble chips in a cement binder.
Rustic Terrazzo: This type showcases a more textured and natural appearance. They often incorporate larger aggregate chips for a rustic, earthy aesthetic.
Aggregate Terrazzo: It consists of a single type of aggregate, such as recycled glass or marble chips, mixed with a binder, resulting in a uniform and minimalist design.
Monolithic Terrazzo: This refers to terrazzo that is poured on-site without any precast or separate installation. It offers seamless, continuous flooring with endless design possibilities.
These are just a few examples, as terrazzo flooring can be customized to meet specific design preferences. This allows for an extensive range of variations and combinations.
Epoxy Terrazzo Flooring
Epoxy terrazzo flooring is a popular choice known for its durability, versatility, and seamless finish. It utilizes an epoxy resin binder mixed with aggregates like marble, quartz, or glass chips, creating a highly customizable surface. Epoxy terrazzo is resistant to stains, chemicals, and moisture, making it ideal for high-traffic areas and contemporary design schemes.
Advantages and applications of Epoxy terrazzo flooring
Epoxy terrazzo floor offers several advantages and finds wide applications in various settings. Its seamless finish eliminates grout lines, making maintenance easier and preventing dirt and bacteria build-up. It is highly durable, resistant to stains, chemicals, and impact. Epoxy terrazzo’s versatility allows for limitless design possibilities, including intricate patterns and vibrant colours. It is commonly used in commercial spaces like airports, hospitals, schools, and retail stores. They are also used in residential projects, due to its aesthetic appeal and long-lasting performance.
Traditional terrazzo or cementitious Terrazzo Flooring
Cementitious terrazzo flooring comes in various types, each offering unique characteristics. Common types include Venetian terrazzo, which features intricate patterns and colourful marble chips; rustic terrazzo, known for its textured and natural appearance; and aggregate terrazzo, using a single type of aggregate like recycled glass or marble chips for a minimalist design. These variations allow for a wide range of aesthetic options to suit different preferences.
Monolithic terrazzo refers to terrazzo flooring that is poured on-site without separate installation or precast elements. It provides a seamless and continuous surface, allowing for unlimited design possibilities and a visually cohesive look.
Advantages of Epoxy Terrazzo Flooring over Cementitious Terrazzo Floor
Here is a comparison between epoxy terrazzo flooring and cementitious terrazzo flooring:
Durability: Epoxy terrazzo has superior chemical and stain resistance, making it more resistant to wear and tear compared to cementitious terrazzo.
Design Versatility: Epoxy terrazzo offers a wider range of design possibilities, including vibrant colours, intricate patterns, and decorative effects, whereas cementitious terrazzo has more limited options.
Seamless Finish: Epoxy terrazzo provides a seamless finish without grout lines, making it easier to clean and maintain compared to cementitious terrazzo.
Installation Time: Epoxy terrazzo has a faster installation process, as it requires less curing time compared to cementitious terrazzo.
Cost: Epoxy terrazzo tends to be more cost-effective than cementitious terrazzo, depending on the complexity of the design and project size.
It’s important to consider specific project requirements and design preferences when choosing between epoxy terrazzo and cementitious terrazzo flooring.
Advantages of Terrazzo Flooring
Terrazzo floor offers several advantages over other popular flooring choices:
Durability: Terrazzo is highly durable and long-lasting, surpassing materials like laminate, vinyl, or carpet.
Design Options: Terrazzo provides endless design possibilities with customizable colours, patterns, and aggregates, unlike the limited options of hardwood or tile.
Low Maintenance: Terrazzo requires minimal maintenance, with easy cleaning and resistance to stains and scratches, unlike carpet or natural stone.
Sustainability: Terrazzo is eco-friendly, often using recycled materials and reducing waste, making it a greener choice compared to some floor options.
Versatility: Terrazzo can be used both indoors and outdoors, accommodating various spaces, while materials like carpet or hardwood may have limited outdoor usage.
Allergen Reduction: Unlike carpet, terrazzo does not trap allergens and is hypoallergenic, promoting a healthier indoor environment.
Longevity: Terrazzo has a long lifespan, exceeding the durability of materials like laminate or vinyl, offering a cost-effective solution over time.
Terrazzo’s unique blend of durability, aesthetic appeal, low maintenance, and sustainability make it stand out among popular flooring choices.
Conclusion
Terrazzo flooring is a versatile, durable, and visually striking option for both residential and commercial spaces. With its timeless appeal and low maintenance, terrazzo floor offers a long-lasting and elegant solution for any design aesthetic.
Flyovers and bridges are essential transportation structures that enable the seamless movement of vehicles and pedestrians. While both serve similar purposes, flyovers navigate intersections efficiently as elevated roads, while bridges connect points over bodies of water or valleys. Their distinct features make them vital components of modern infrastructure. This article is about the features and advantages of Flyovers and bridges and the difference between flyovers and bridges.
A flyover, also referred to as an overpass or an elevated roadway, is a transportation infrastructure that provides a dedicated elevated route for vehicles to traverse over obstacles such as intersections, congested areas, or other roads.”Designers create flyovers to enhance traffic flow, reduce congestion, and improve overall transportation efficiency.”
Constructors typically build flyovers above ground level, enabling vehicles to bypass busy intersections or intersections with heavy pedestrian traffic. Generally, by separating the flow of vehicles from crossroads and pedestrian crossings, flyovers minimize traffic conflicts and ensure uninterrupted movement. This in turn results in smoother traffic flow, reduced delays, and improved safety.
The construction of flyovers requires careful planning and engineering. Generally, builders often use reinforced concrete or steel girders to construct flyovers, providing structural support for vehicles and the ability to bear substantial loads. The design includes ramps or access points to enable smooth vehicle entry and exit onto the flyover, ensuring seamless integration with the current road network.
What are the benefits of flyovers?
The benefits of flyovers include:
Improved traffic flow: Basically, Flyovers separate the flow of vehicles, reducing congestion and ensuring smoother traffic movement.
Reduced travel time: By bypassing intersections or congested areas, flyovers enable faster and more efficient travel, saving time for commuters.
Enhanced safety: Flyovers minimize the risk of accidents by eliminating conflict points between vehicles and pedestrians or conflicting traffic streams.
Increased capacity: Flyovers can increase the capacity of road networks by providing additional lanes or routes for vehicles.
Better fuel efficiency: Reduced congestion and smoother traffic flow on flyovers contribute to improved fuel efficiency and reduced emissions.
Enhanced connectivity: Flyovers connect different parts of a road network, improving accessibility and connectivity between areas.
Improved urban aesthetics: Well-designed flyovers with landscaping, architectural features, and decorative elements can enhance the visual appeal of urban landscapes.
Economic benefits: Efficient traffic flow facilitated by flyovers can boost economic productivity by reducing transportation costs and improving logistics.
Minimized environmental impact: Generally, flyovers can help reduce air pollution and noise pollution by minimizing congestion and idling time at intersections.
Improved emergency response: Flyovers provide unimpeded routes for emergency vehicles, enabling quicker response times during emergencies or disasters.
Types of flyovers
Flyovers are classified based on the following factors
a) Classification based on the formation
b) Classification based on materials
Straight Flyovers: Follow a straight-line trajectory, providing a direct route over obstacles.
Curved Flyovers: Incorporate curves or bends in their design, accommodating specific road alignments or geographical constraints.
T-Junction Flyovers: Connect perpendicular roads at a T-junction, allowing for uninterrupted traffic flow in multiple directions.
Cloverleaf Flyovers: Form a circular or cloverleaf-shaped interchange, facilitating smooth merging and diverging movements between roads.
Diamond Flyovers: Feature a diamond-shaped interchange, allowing for efficient access and exits from multiple directions.
Multi-Level Flyovers: Comprise multiple layers or levels, providing complex interchanges with ramps and access points for different roads.
U-Turn Flyovers: Enable U-turns or reverse movements, allowing vehicles to change direction without disrupting traffic flow.
Classification of flyovers based on Materials
Prestressed Concrete Flyovers: Constructed using precast prestressed concrete segments that provide strength and durability.
Steel Flyovers: Built using steel girders, offering flexibility in design and allowing for longer spans.
Reinforced Concrete Flyovers: Constructed using reinforced concrete beams or slabs, offering a balance between cost, strength, and ease of construction.
Composite Flyovers: Combination of steel and concrete elements, leveraging the advantages of both materials for optimal structural performance.
Cable-Stayed Flyovers: Supported by cables attached to tall towers, offering an elegant and efficient structural solution for longer spans.
Box Girder Flyovers: Consists of hollow box-shaped beams, providing strength, rigidity, and resistance against bending and torsion forces.
Extradosed Flyovers: Hybrid of cable-stayed and prestressed concrete flyovers featuring shorter towers and fewer cables while maintaining structural integrity.
What are bridges?
Engineers design bridges to connect two points over a body of water, a valley, or any physical obstacle. They typically comprise abutments, piers, and a deck or roadway for transportation. The construction of bridges involves using diverse materials like concrete, steel, or wood, which depend on factors such as span length and the required load capacity. However, They serve as crucial transportation links, facilitating the passage of vehicles, pedestrians, and sometimes, even trains. Bridges provide essential connectivity, improve accessibility, promote trade, and enable social and economic development by overcoming natural barriers and creating efficient transportation routes.
Here are the key differences between flyovers and bridges
Purpose
Bridges
Flyover
Bridges are primarily built to connect two points over a body of water, a valley, or any physical obstacle.
Flyovers are constructed to navigate intersections, congested areas, or other roads efficiently, providing an elevated route for vehicles.
Purpose
Design of flyovers and bridges
Bridge
Flyover
Bridges are typically designed with piers or support that span across the obstacle, supporting a deck or roadway.
Flyovers are designed as elevated roadways, often supported by columns or piers, allowing vehicles to bypass intersections or congested areas.
Design
Location of flyovers and bridges
Bridge
Flyover
Bridges are commonly found over bodies of water, such as rivers, lakes, or seas, or in areas with significant topographical variations like valleys or canyons.
Flyovers are usually constructed in urban areas with heavy traffic, where they can provide efficient bypasses for intersections or congested road segments.
Location
Traffic Flow of flyovers and bridges
Bridge
Flyover
Bridges accommodate two-way traffic, allowing vehicles to travel in both directions.
Flyovers typically facilitate one-way traffic flow, with separate lanes or ramps for entering and exiting.
Traffic flow
Integration
Bridge
Flyover
Bridges are integrated into the existing road network, connecting two points and providing a continuous route.
Flyovers are designed to integrate with existing roads, providing seamless connectivity by allowing vehicles to enter and exit at designated access points.
Integration
Environmental Factors
Bridge
Flyover
Bridges often need to consider factors like water flow, tidal forces, or seismic activity, depending on their location.
Flyovers focus on addressing traffic congestion and improving transportation efficiency, with less consideration for natural elements.
Environmental factors
Length and Span
Bridge
Flyover
Bridges can vary in length and span depending on the distance they need to cover, ranging from short spans to long suspension or cable-stayed bridges.
Flyovers are generally shorter in length compared to bridges, spanning a specific area such as an intersection or congested road segment.
Length and span
Understanding these distinctions can help in determining the appropriate infrastructure solution based on the specific transportation needs and challenges of a given location.
Constructing a building involves several stages, including preconstruction and post-construction phases. The preconstruction stage encompasses project initiation, design and planning, obtaining permits and approvals, and procurement and contracting. It sets the foundation for successful construction by defining objectives, creating designs, securing necessary permissions, and selecting contractors.
Constructing a building encompasses the physical execution of the project, involving activities like excavation, structural construction, and interior finishes. Post-construction activities include testing and inspections, occupancy and commissioning, documentation, and ongoing maintenance. These stages ensure that the building meets quality standards, adheres to regulations, and functions optimally for its intended purpose. This article is about the preconstruction and post-construction stages of a building.
Constructing a building – Steps involved
Pre-construction and post-construction stages are the major stages involved in constructing a building.
Preconstruction steps in Constructing a building
Project Initiation
Feasibility Study
Design Development
Permitting and Approvals
Cost Estimation
Value Engineering
Scheduling
Procurement and Contracting
Project initiation
Project initiation is the first step in building construction, involving assessing project needs, conducting feasibility studies, identifying stakeholders, defining objectives, and securing initial funding. It sets the foundation for a successful project by determining its viability, scope, and initial direction.
Feasibility study
The feasibility study is a process in building construction that evaluates the practicality and potential success of a project. It involves analyzing various factors such as financial viability, market demand, site suitability, environmental impact, and legal considerations. The study helps determine if the project is viable and worth pursuing.
Design Development for constructing a building
Design development is a phase in building construction where preliminary design concepts are further developed into detailed designs. It involves refining architectural and engineering plans, selecting materials, incorporating structural elements, and addressing functional requirements. The goal is to create comprehensive and accurate designs that meet the project objectives.
Permitting and Approvals for constructing a building
Permitting and approvals are essential steps in building construction that involve obtaining the necessary permits, licenses, and approvals from relevant authorities. This includes submitting architectural plans, environmental impact assessments, and other required documentation to ensure compliance with building codes, regulations, and zoning ordinances.
Cost Estimation for Constructing a Building
Cost estimation is the process of estimating the total expenses associated with a building construction project. It involves analyzing various factors such as materials, labour, equipment, permits, and overhead costs to determine the overall project cost. Accurate cost estimation helps in budgeting and financial planning for the construction project.
Value Engineering for constructing a building
Value engineering is a systematic approach used in building construction to optimize the value and efficiency of a project. It involves reviewing the design, materials, and construction methods to identify opportunities for cost savings, improved functionality, and enhanced performance while maintaining the project’s objectives and quality standards.
Scheduling
Scheduling in building construction refers to the process of creating a timeline and sequence of activities to guide the construction project. It involves identifying the necessary tasks, estimating their durations, and determining their interdependencies to ensure efficient resource allocation, coordination, and timely completion of the project.
Procurement and Contracting
Procurement and contracting in building construction involve the selection and acquisition of materials, equipment, and services necessary for the project. It includes preparing bid documents, soliciting proposals from suppliers and subcontractors, evaluating offers, negotiating contracts, and awarding agreements. Effective procurement and contracting ensure the availability of resources and adherence to project specifications and timelines.
During construction steps in Constructing a building
During the construction stage of building construction, the following steps are typically undertaken:
Site Preparation
Excavation and Foundation Work
Structural Construction
Installation of Utilities (Electrical, Plumbing, HVAC)
Exterior and Interior Finishes
Flooring and Wall Finishes
Installation of Fixtures and Equipment
Final Inspections and Quality Control
Site Cleanup and Waste Disposal
These steps involve the physical execution of the building project, transforming the design and plan into a completed structure. Each step requires coordination, skilled labour, and adherence to safety and quality standards.
Site preparation for constructing a building
Site preparation is the initial phase of construction where the building site is prepared for construction activities. It involves clearing vegetation, levelling the ground, establishing access points, and implementing necessary safety measures to create a suitable and safe work environment.
Excavation and Foundation Work
Excavation and foundation work is a critical phase of construction involving the digging of trenches, removal of soil, and construction of the foundation. This process provides a stable base for the building and prepares the site for further construction activities.
Structural Construction
Structural construction is a crucial phase in building construction that involves the assembly and construction of the building’s structural elements. It encompasses several key steps:
Formwork: Creating temporary structures (formwork) to shape and support concrete during pouring and curing.
Reinforcement Installation: Placing steel reinforcement bars (rebar) within the formwork to provide strength and structural integrity.
Concrete Pouring: Pouring concrete into the formwork, ensuring proper placement and compaction.
Curing: Allowing the concrete to cure and gain strength over time through hydration.
Column and Beam Construction: Erecting columns and beams to support the building’s framework, ensuring accurate alignment and connection.
Slab Construction: Building horizontal slabs, such as floor slabs, roof slabs, and intermediate slabs, providing structural support and functional surfaces.
Wall Construction: Constructing load-bearing or non-load-bearing walls using materials like concrete blocks, bricks, or precast panels.
Staircase and Elevator Shaft Construction: Building vertical circulation elements, such as staircases and elevator shafts, ensuring safety and accessibility.
Roof Construction: Installing the roof structure, including trusses, beams, and roofing materials, to provide shelter and protect the building.
Quality Control: Conducting inspections and tests to ensure structural integrity, adherence to building codes, and safety standards.
Structural construction is a critical phase that lays the foundation for the building’s overall strength and stability, supporting subsequent construction activities and the realization of the final structure.
Installation of Utilities (Electrical, Plumbing, HVAC)
The installation of utilities, including electrical, plumbing, and HVAC (Heating, Ventilation, and Air Conditioning) systems, is a vital phase in building construction. It involves the placement and connection of electrical wiring, fixtures, and outlets; the installation of plumbing pipes, fixtures, and drainage systems; and the set up of HVAC equipment for heating, cooling, and ventilation to ensure functionality and comfort within the building.
Exterior and Interior Finishes
During the exterior and interior finishes phase of building construction, the building’s surfaces are enhanced and protected. Exterior finishes include the application of materials like paint, siding, stucco, or cladding to provide weather resistance and aesthetics. Interior finishes involve installing flooring, wall finishes, ceilings, and other decorative elements to create a visually appealing and functional space inside the building.
Flooring and Wall Finishes
During the flooring and wall finishes phase of building construction, the surfaces are transformed to enhance aesthetics, durability, and functionality. Flooring involves installing materials such as tiles, hardwood, or carpeting. Wall finishes include applying paint, wallpaper, or decorative panels. These finishes contribute to the overall appearance and ambience of the interior spaces.
Installation of Fixtures and Equipment
During the installation of fixtures and equipment phase of building construction, various fixtures and equipment are installed to make the building functional and ready for use. This includes fitting and connecting items like lighting fixtures, plumbing fixtures, cabinetry, appliances, and other necessary equipment to ensure the building is equipped and operational for its intended purpose.
Final Inspections and Quality Control
During the final inspections and quality control phase of building construction, thorough inspections are conducted to ensure compliance with building codes, regulations, and quality standards. This involves reviewing the construction work, checking for any defects or deficiencies, and verifying that all systems and components meet the required standards. It ensures that the building is safe, functional, and meets the expected quality levels before occupancy or handover.
Site Cleanup and Waste Disposal
Site cleanup and waste disposal is the final step in building construction. It involves removing construction debris, cleaning the site, and properly disposing of waste materials in accordance with environmental regulations to restore the site to a safe and clean condition.
Post-construction steps in Constructing a building
Testing and Inspections
Certificate of Occupancy
Commissioning
Handover and Documentation
Post-Occupancy Evaluation
Maintenance and Facility Management
Testing and Inspections
Testing and inspections involve conducting assessments to verify the quality and functionality of various building systems, components, and installations.
Certificate of Occupancy
A Certificate of Occupancy is a document issued by local authorities after the final inspections, indicating that the building meets all relevant codes and regulations, and is deemed safe and suitable for occupancy.
Commissioning
Commissioning is the process of ensuring that all building systems, equipment, and components are installed, tested, and functioning properly. It involves verifying their performance, efficiency, and compliance with design and operational requirements before the building is occupied.
Handover and Documentation
Handover and documentation is the process of transferring the completed building to the owner or client. It involves providing all relevant documents, records, and manuals, ensuring a smooth transition, and formally concluding the construction project.
Post-Occupancy Evaluation
Post-occupancy evaluation is the assessment of a building’s performance, functionality, and user satisfaction after it has been occupied. It involves gathering feedback, identifying areas for improvement, and informing future design and construction decisions.
Maintenance and Facility Management
Maintenance and facility management involves the ongoing upkeep and management of the building and its systems. This includes routine inspections, repairs, and maintenance activities to ensure the building remains in optimal condition, meets operational requirements, and provides a safe and comfortable environment.
IPS flooring, also known as Indian Patent Stone flooring, is a popular type of flooring widely used in commercial and industrial spaces. It is a durable, cost-effective solution providing a smooth surface. IPS floor consists of a mixture of cement, aggregates, and pigments, which is poured onto a prepared base and then finished to achieve the desired level and texture. It offers excellent strength, resistance to heavy loads, and easy maintenance, making it suitable for areas with high foot traffic. IPS floor is a reliable choice for creating functional and aesthetically appealing floors in various settings.
IPS flooring offers several key features that make it a popular choice:
Durability: IPS floor is highly durable and can withstand heavy loads and constant foot traffic, making it ideal for commercial and industrial spaces.
Cost-effective: It is a cost-effective flooring option compared to alternatives like marble or tiles, making it a budget-friendly choice for many projects.
Easy maintenance: IPS floor requires minimal maintenance, with regular cleaning being sufficient to keep it in good condition.
Versatility: It can be customized to achieve various textures, patterns, and colours, allowing for creative design possibilities.
Strength: IPS floor provides excellent stability and resistance to wear, making it suitable for areas that require long-lasting flooring solutions.
Installation flexibility: It can be poured and finished on-site, allowing for customization and adaptation to the specific requirements of the space.
Eco-friendly: IPS floor is made from natural materials like cement and aggregates, making it an environmentally friendly flooring option.
Non-slip properties: The texture of the IPS floor provides a non-slip surface, enhancing safety in areas prone to moisture or spills.
Types of IPS Floors
IPS flooring offers various types to suit different requirements:
Plain IPS Floor: It is the standard type, providing a smooth and level surface suitable for most applications.
Coloured IPS Floor: We add pigments or dyes to the IPS mixture, which enables us to create customized colours and explore various decorative possibilities.
Decorative IPS Floor: This type incorporates designs, patterns, or logos into the flooring, adding aesthetic appeal to the space.
Epoxy IPS Flooring: The IPS mixture enhances durability, and chemical resistance, and provides a glossy finish by mixing epoxy resin with it.
Stamped IPS Flooring: During the finishing process, texture mats or stamps create patterns resembling natural materials like stone, brick, or wood.
Polished IPS Flooring: To achieve a smooth and shiny finish that enhances the overall appearance, we use abrasives to polish the surface.
Anti-static IPS Flooring: It contains special additives to minimize static electricity, making it suitable for sensitive electronic environments.
Self-levelling IPS flooring pours and spreads evenly, levelling itself automatically to create a smooth and seamless surface.
Main ingredients of IPS floor
IPS flooring typically consists of a mixture of cement, aggregates, pigments, and water. The specific proportions of these ingredients may vary depending on the desired strength and characteristics of the flooring. Cement acts as a binding agent, while aggregates like sand and crushed stone provide stability and strength. To achieve desired colours or decorative effects, you add pigments. You use water to mix the ingredients into a workable consistency. Additionally, you can include additives like plasticizers or admixtures to enhance workability, improve curing, or provide specific properties such as water resistance or chemical resistance.
Strips in IPS flooring
Strips in IPS floor serve as control joints or expansion joints. These strips serve the purpose of accommodating the natural movement and expansion of the flooring due to temperature changes. They are commonly made of materials such as PVC, glass, or metal and are installed to fulfil this function. These strips help prevent cracking and maintain the structural integrity of the IPS flooring.
Strips, such as control joints or expansion joints, are highly recommended for IPS floors. While not always mandatory, they serve important purposes in ensuring the long-term durability and integrity of the flooring. These strips accommodate the natural movement and expansion of the floor due to temperature changes, preventing cracks and structural damage. Additionally, they help control the formation of shrinkage cracks and provide a designated area for any potential future repairs or modifications. The utilization of strips is generally regarded as beneficial and advisable for installations of IPS flooring.
PVC Strips: PVC (Polyvinyl Chloride) strips are commonly used as control joints in IPS flooring. They provide flexibility, durability, and resistance to moisture, making them suitable for various applications.
Metal Strips: Metal strips, often made of aluminium or stainless steel, offer strength and stability. They provide effective control joints and can withstand heavy loads and traffic.
Rubber Strips: Rubber strips are flexible and offer excellent shock absorption and noise reduction properties. They are commonly used in areas where vibration control and comfort are important.
Fibre Strips: Fiber strips, made from materials like fibreglass or carbon fibre, offer high tensile strength and resistance to cracking. They are commonly used as expansion joints in IPS flooring.
Foam Strips: Foam strips, typically made of closed-cell polyethylene foam, provide cushioning and flexibility. They are effective in absorbing impact and reducing noise transmission in IPS flooring.
Installation methodology of IPS flooring
The installation methodology of IPS flooring typically involves the following steps:
Surface Preparation: Thoroughly clean the existing floor surface, ensuring it is free from dust, dirt, grease, or any other contaminants. Remove any loose or damaged portions if necessary.
Base Preparation: Prepare a base layer using a mixture of cement and coarse sand. Spread it evenly on the cleaned surface, compacting and levelling it to establish a stable foundation for the IPS flooring.
Mixing IPS Mixture: Combine cement, aggregates (such as fine sand and crushed stone), pigments (if desired), and water to prepare the IPS mixture. Thoroughly mix until achieving a consistent and workable consistency.
Pouring and Spreading: Pour the mixed IPS mixture onto the prepared base in sections. Spread and level it using trowels or screeding techniques to achieve the desired thickness and evenness.
Finishing: Use tools like trowels or power floats to smoothen the surface, eliminating imperfections. Apply texture or pattern stamps if desired.
Curing: Allow the freshly installed IPS flooring to cure for a specific period. Cover it with a curing compound or use wet curing methods to ensure proper hydration and strength development.
Cleaning and Sealing: After the curing period, clean the surface to remove any residue or loose particles. Consider applying an appropriate sealant to enhance the durability and stain resistance of the IPS flooring.
It’s important to note that the exact installation methodology may vary depending on specific project requirements and the recommendations provided by the manufacturer or flooring experts.
Reinforced Cement Concrete or RCC is a versatile and widely used construction material. RCC combines concrete’s compressive strength with steel reinforcement’s tensile strength. It forms by mixing cement, aggregates, water, and steel reinforcement bars to create a composite material. RCC is known for its excellent structural performance, durability, fire resistance, and other environmental factors. The steel reinforcement provides added strength and prevents cracking and failure under loads. Engineers extensively utilize RCC to construct buildings, bridges, dams, and other structures. This makes RCC an essential component in modern construction engineering.
This article is about Reinforced Cement Concrete (RCC) , applications, advantages and disadvantages.
Reinforced Cement Concrete (RCC) Full form – Introduction
Reinforced Cement Concrete (RCC) widely combines concrete’s strength with steel reinforcement as a construction material. It forms by mixing cement, aggregates, water, and steel rebars. RCC earns renown for its durability, versatility, and excellent structural performance. Concrete provides compressive strength, while steel reinforcement enhances tensile strength, preventing cracks and failures. Engineers strategically place the steel rebars within the concrete to withstand different types of loads. RCC offers benefits such as fire resistance, weathering resistance, and chemical durability. It finds application in various construction projects, including buildings, bridges, dams, and tunnels. Its versatility allows for flexible design and construction, accommodating different shapes and complexities. RCC plays a vital role in modern construction engineering as it provides a strong and reliable material for creating long-lasting and resilient structures.
Ingredients of Reinforced Cement Concrete (RCC)
Reinforced Cement Concrete (RCC) incorporates the following ingredients.
Cement,
aggregates (such as sand and gravel),
water,
steel reinforcement bars (rebars)
Admixures
Cement
In reinforced cement concrete (RCC), engineers use cement as the binding agent that holds together the aggregates and steel reinforcement. Cement imparts strength and durability to the RCC, making it suitable for various construction applications like buildings, bridges, dams, and infrastructure projects.
Aggregates
Aggregates are used in reinforced cement concrete (RCC) to provide bulk and stability. They fill the gaps between the cement particles, adding strength to the concrete mix. Aggregates also help in reducing shrinkage and controlling the workability of the mixture, making it suitable for construction applications such as buildings, roads, and foundations.
Aggregates can be classified into two categories: fine aggregates and coarse aggregates. Fine aggregates, such as sand, have particle sizes smaller than 4.75 mm, while coarse aggregates, like gravel or crushed stone, have particle sizes ranging from 4.75 mm to 80 mm. This classification is based on particle size and is important for achieving the desired workability and strength in concrete mixtures.
Water
Water is a crucial component in reinforced cement concrete (RCC). It is used to hydrate the cement, initiating the chemical reaction that forms a solid matrix. Water also enables the workability of the concrete mix, making it easier to pour, place, and compact. Proper water-cement ratio ensures optimal strength and durability of the RCC.
Reinforcement bars or rebars
Reinforcement plays a vital role in reinforced cement concrete (RCC) by enhancing its tensile strength. Steel reinforcement bars (rebars) are embedded within the concrete to resist tensile stresses and prevent cracking. The combination of concrete’s compressive strength and steel’s reinforcing properties ensures the structural integrity and durability of the RCC.
Admixures
Admixtures are additives used in reinforced cement concrete (RCC) to modify its properties. They can improve workability, reduce water content, enhance strength, control setting time, or provide special characteristics like waterproofing or corrosion resistance. Admixtures allow engineers to optimize the performance and durability of RCC in various construction applications.
Advantages of Reinforced Cement Concrete (RCC)
Reinforced Cement Concrete (RCC) offers several advantages in construction.
Firstly, it combines the compressive strength of concrete with the tensile strength of steel reinforcement, making it highly durable and resistant to cracking.
RCC can withstand heavy loads and offers excellent structural performance. It also exhibits fire resistance, weathering resistance, and durability against environmental factors.
RCC can be molded into various shapes and sizes, allowing for flexible and versatile construction designs.
The use of steel reinforcement prevents sudden failures and enhances the overall strength of the structure. Overall, RCC is a reliable and widely used construction material that provides long-lasting, resilient, and safe structures.
Disadvantages of RCC
While Reinforced Cement Concrete has numerous advantages, it also has certain disadvantages.
Firstly, RCC structures require skilled labor and meticulous construction techniques, which can increase costs.
The use of steel reinforcement adds to the weight of the structure, potentially leading to higher transportation and foundation costs.
Another disadvantage is the susceptibility of steel reinforcement to corrosion over time, requiring proper maintenance and protection measures.
Additionally, RCC structures may have limited flexibility in terms of alterations or modifications compared to other construction materials.
Lastly, the production of cement, a key component of RCC, involves high carbon emissions, contributing to environmental concerns.
Despite these disadvantages, proper design, construction, and maintenance practices can mitigate these issues and ensure the longevity and performance of RCC structures.
Reinforced Cement Concrete
Properties of RCC
Reinforced Cement Concrete exhibits several desirable properties that make it a widely used construction material.
Firstly, it possesses excellent compressive strength, enabling it to withstand heavy loads.
RCC also benefits from the tensile strength provided by steel reinforcement, preventing cracks and enhancing overall structural performance. Moreover, It offers durability and resistance to fire, weathering, and chemical attacks.
Additionally, RCC has good thermal and sound insulation properties, contributing to the comfort and safety of structures. It provides versatility in design and construction, allowing for flexibility in creating various shapes and sizes.
Overall, the properties of RCC make it a reliable and preferred choice for a wide range of construction applications.
Grit Chambers are one of the most commonly used types of equipment in the wastewater treatment process. In this blog, I will walk you through the mechanism, types and uses of grit chambers. Before diving deep into grit chambers, make sure that you go through these blogs so that you know what exactly happens in a wastewater treatment plant.
Grit chambers are settling tanks or basins that collect the inorganic particles and avoid their accumulation in sludge digesters as well as prevent damage to the pumps. Grit will damage pumps by abrasion and cause serious operational difficulties in sedimentation tanks and sludge digesters as it can accumulate around outlets and pump suction thereby choking them. Consequently, it is common practice to remove this material by grit chambers.
We usually place them ahead of pumps or comminuting devices. Mechanically cleaned grit chambers should be preceded by coarse bar rack screens. We typically design the Grit chambers as a long channel in which we reduce, the wastewater’s velocity sufficiently to deposit heavy inorganic solids but to retain organic material in suspension. Channel-type chambers should provide controlled velocities as close as possible to 1.0 feet per second. Velocities substantially more significant than 1.0 feet per second cause excessive organic materials to settle out with the grit. The detention period is usually between 20 seconds to 1.0 minutes.
Grit Chambers Working Principle
The critical velocity of flow should always be lesser than the critical scouring velocity so that the inorganic particles settle.
Grit Chamber Types
We can classify grit chambers into two types, depending on the cleaning mechanism.
Mechanically cleaned
A mechanically cleaned grit chamber uses mechanical means to remove the accumulated grit. Scraper blades in a mechanically cleaned grit chamber collect the grit that has accumulated on the chamber’s floor. By using various devices such as bucket elevators, jet pumps, and airlifts, we can raise this grit to ground level and remove them. The grit washing mechanisms mostly include agitation tools that use either water or air to provide washing action.
Manually Cleaned
In the manually cleaned Grit chamber, we remove the grit manually using a shovel. We must clean them at least once each week. Also, they should have adequate capacity for storing grits between the time of cleaning.
Based on the mode of operation, we can classify grit chambers as follows:
Horizontal Flow Grit Chambers
These are long narrow tanks about 10-18 meters long and 1 to 1.3 m in depth and rely on gravity to settle out the heavy solids. The wastewater is directed into the tank at a controlled rate and the velocity is kept low to allow the particles to settle to the bottom of the tank. We remove the settled material with a scraper mechanism or airlift pump.
Aerated Grit Chambers
Aerated grit chambers use a combination of mechanical mixing and agitation with air to prevent the solids from settling and keep them in suspension. After mixing with air, the mixture flows into a settling zone to separate the solids. The diffusers are located at about 0.45 to 0.6 m from the bottom. Wastewater moves in the tank in a helical path and makes two or three passes across the bottom of the tank at maximum flow. Wastewater is introduced in the direction of roll in the grit chamber. This type of grit chamber has grit removal grab buckets, travelling on monorails over the grit collection and storage trough. We can also use chain and bucket conveyors.
Typical design details for the aerated grit chamber are :
Depth: 2 to 5 m
Length: 7.5 to 20 m
Width: 2.5 to 7.0 m
Width to depth ratio: 1:1 to 5:1
Air supply m3 /m.min of length: 0.15 to 0.45 (0.3 typical)
Detention time at peak flow: 2 to 5 min (3 minutes typical)
Vortex Type Grit Chambers
In this grit is removed with a vortex flow pattern. The wastewater enters tangentially and exits in the perpendicular direction of motion either from the top or from the side. Due to inertia, the grit particle will remain in the chamber and liquid free from grit will only escape. The rotating turbine maintains constant velocity and helps in separating organic matter and grit. We get washed grit, free from the organic matter from this device.
Now, let’s have a look at the uses of grit chambers.
Grit Chamber Uses
The uses of the grit chamber are as follows:
Prevents equipment from clogging.
Slow down the flow to settle heavy solids.
Saves the wastewater treatment cost.
Controls grit collection in sludge digesters.
Conclusion
In this blog, we saw the working principle, types and uses of grit chambers. If you have any queries please feel free to ask in the comments section.
Tensile structures or Tension in structures refers to the internal force created within a structure due to an applied load that tends to pull or stretch the structural members apart. When a force is applied in tension to a structure, the structural elements experience a stretching effect, which creates tensile stress within the material. This stress can cause the material to deform, and if the tension becomes too great, it can cause the material to fail or break.
Tension is a critical consideration in structural design, and engineers must carefully calculate and account for the amount of tension that a structure will experience in order to ensure that it can withstand the anticipated loads without failing. Materials such as steel, which have high tensile strength, are often used in structures that will be subjected to significant tensile forces.
When studying architecture/civil engineering, you often come across the concepts of tension and compression, which are two types of forces. The majority of structures we construct are in compression, meaning that they rely on the downward pressure and squeezing of materials such as bricks and boards to remain stable on the ground. In contrast to compression, tension involves the pulling and stretching of building materials.
Some of the earliest human-made shelters have historically influenced tensile structures. For instance, the nomads of the Sahara Desert, Saudi Arabia, and Iran developed black tents using camel leather. Native American tribes also built various structures. Compared to other structural models, tensile structures provide several advantages, and they are inspired by these ancient shelters.
The principle of tensile structures is that they rely on tension to create a stable structure. Tensile structures use tensioned elements, such as cables, ropes, or membranes, to transmit loads and create a self-supporting structure. These tensile elements are anchored to supports, such as poles or columns. The supports resist the tensile forces and keep the structure in place. The tensioned elements work together to distribute the load and create a structurally efficient system. Tensile structures are known for their lightweight and flexible design, which allows them to span long distances while using minimal materials.
Types of tensile structure
Tensile structures can be classified based on the plane in which the tensile forces act, which determines the shape and form of the structure. The three main classifications of tensile structures based on the plane of tension are:
Linear Tensile Structure
Tensioned cables or rods support a linear tensile structure, which is a type of lightweight and flexible structure characterized by long, narrow spans. These structures are often used to provide shade or cover for outdoor spaces such as pedestrian walkways, seating areas, or parking lots. Designers typically aim for a simple, minimalist aesthetic and can use a range of materials, including steel cables, high-strength polyester fabric, or PTFE-coated fiberglass. The design of linear tensile structures is important to ensure stability and resistance to wind, snow, and other loads. Engineers use computer simulations and physical testing to determine the optimal shape, size, and materials for the structure.
Shade sails: Tensioned fabric structures used to provide shade in outdoor spaces.
Tensile canopies: Lightweight fabric structures used to provide shade or cover for outdoor events.
Tensile bridges: Tensioned cables or rods support pedestrian or cycle bridges.
Tensile roofs: Tensioned fabric structures used to cover large outdoor spaces.
Tensile facades: One can attach external lightweight fabric or cable structures to a building’s exterior. Their purpose is to provide shade or reduce solar heat gain.
Three-dimensional tensile structures
Designers create a three-dimensional tensile structure with multiple curved surfaces in three dimensions. Manufacturers make 3D tensile structures from various materials such as fabric, steel, and composites. Architects frequently utilize these structures in large-scale projects such as stadiums, airports, and exhibition halls.
Cone-shaped structures: Three-dimensional structures shaped like a cone, often used for small pavilions or temporary structures.
Hyperbolic paraboloid structures: Curved structures with a saddle shape that can span large areas, used in roofs and canopies.
Geodesic dome structures: Spherical structures made of interconnected triangles, used for large span structures such as greenhouses or exhibition spaces.
Cable-net structures: Three-dimensional networks of tensioned cables that can form complex curved shapes, used for roofs and facades.
Pneumatic structures: Three-dimensional structures made of airtight materials, inflated to create a stable shape, often used for temporary structures such as exhibition booths.
Surface-Stressed Tensile Structures
Designers create surface-stressed tensile structures with pre-stressed fabric or membrane panels.” They tension the panels in all directions to create a stable and self-supporting three-dimensional surface. “Large-scale projects like stadiums, arenas, or exhibition halls often use this type of structure, which designers can make from various materials such as PVC-coated polyester, PTFE-coated fiberglass, or ETFE foil. “The pre-stressing of the fabric panels allows for the creation of complex shapes and curves, making surface-stressed tensile structures a popular choice for architects and designers looking to create visually striking and functional structures.
Single-curved surface-stressed structures: Designers often use a pre-stressed membrane to create a stable, self-supporting structure with a single curved surface for roofing applications or canopies.
Double-curved surface-stressed structures: These structures have two curved surfaces that intersect, creating complex shapes and curves. They are often used for large-scale architectural projects such as stadiums, exhibition halls, or museums. The designer creates a stable, self-supporting structure by tensioning a pre-stressed membrane in multiple directions for double-curved surface-stressed structures.
Shapes of tensile structures
The basic shapes of tensile structures include:
Cone – a structure shaped like a cone with a pointed top.
Hyperbolic paraboloid – a saddle-shaped structure that can span large areas.
Cylindrical – a structure shaped like a cylinder with rounded ends.
Spherical – a structure shaped like a sphere.
Pyramid – a structure with a base that is a polygon and triangular sides that meet at a point. One can create more complex shapes and designs for tensile structures by combining or modifying these shapes.
Major tensile structures around the world
The Sydney Opera House – a famous example of a double-curved surface-stressed tensile structure, with sail-shaped roofs.
The Denver International Airport – a cable-net structure featuring a white fabric roof spanning over 500,000 square feet.
The Olympic Stadium in Munich – a tensile membrane structure with an acrylic glass roof held by a steel tension ring.
The Burj Khalifa – a skyscraper featuring a helix-shaped tensile structure at its base, designed to withstand high wind loads.
The Kauffman Center for the Performing Arts – a cone-shaped tensile structure that covers an outdoor courtyard and serves as a performance venue.
Advantages of Tensile structures
Tensile structures offer several advantages over traditional building structures, including:
Lightweight: Compared to traditional building materials, tensile structures are lightweight, which can lead to lower transportation and installation costs.
Flexibility: The flexibility of the materials used in tensile structures allows for the creation of unique and complex shapes, which can be difficult or impossible to achieve with traditional building materials.
Durability: Designers create tensile structures to endure harsh weather conditions, which makes them a durable and long-lasting option.
Cost-effective: The lightweight materials and quick installation time of tensile structures can result in lower construction costs compared to traditional building structures.
Energy efficiency: Tensile structures allow for natural light to penetrate, reducing the need for artificial lighting and making them energy-efficient.
Sustainable: Manufacturers can make tensile structures from recyclable materials and can easily dismantle and reuse them, making them a sustainable option for construction.
Azeotropes or azeotropic mixtures have always been a topic of interest due to their unique properties and the inability to separate them completely using conventional distillation. A classic example of azeotropes occurs in winemaking wherein an Ethanol-water mixture forms an azeotropic mixture at 96% Ethanol by volume which prohibits its further purification by distillation. In this blog, let’s look at how this happens and how we can separate such azeotropic mixtures.
Before diving into azeotropes and azeotropic distillation, let’s have a quick look at the distillation process.
Azeotropes are constant boiling point mixtures. Azeotropes are mixtures of two or more liquids whose composition cannot be altered or changed by simple distillation. This occurs because the vapour’s constituent ratios are identical to those of the unboiled mixture when an azeotrope is boiled. Azeotropes are also known as constant boiling point mixtures since distillation leaves their composition unaltered.
There is a distinctive boiling point for each azeotrope. An azeotrope’s boiling point is either lower or higher than the boiling points of any of its constituents. Depending on the boiling point deviation, we have two types of azeotropes as follows:
Maximum boiling azeotropes
Maximum boiling azeotropes are those mixtures that have a boiling point higher than any of their constituents. These azeotropes show a large negative deviation from Raoult’s Law. So we can call them negative azeotropes or pressure minimum azeotropes.
Hydrochloric acid at a concentration of 20.2% and 79.8% water (by mass) is an example of a negative azeotrope. Water and hydrogen chloride both boil at 100 °C and 84 °C, respectively, but the azeotrope boils at 110 °C, exceeding the boiling points of both of its ingredients. Any hydrochloric acid solution can boil at a maximum temperature of 110 °C. Other negative azeotropes include:
Nitric acid (68%)/water, which boils at 120.2 °C at 1 atm
Hydrofluoric acid (35.6%)/water, which boils at 111.35 °C
Water with perchloric acid (71.6%), 203 °C boiling point
Water and sulfuric acid (98.3%), boiling at 338 °C
Minimum boiling azeotropes are those mixtures that have a boiling point higher than any of their constituents. These azeotropes show a large positive deviation from Raoult’s Law. So we can call them positive azeotropes or pressure maximum azeotropes.
The mixture of 95.63% ethanol and 4.37% water (by mass), which boils at 78.2 °C, is a well-known example of a positive azeotrope. The azeotrope boils at 78.2 °C, which is lower than any of its components as ethanol boils at 78.4 °C and water boils at 100 °C.
Azeotropic Distillation
Since the vapours of azeotropes produced after boiling have the same composition as that of its liquid mixture, conventional distillation techniques can’t separate azeotropes. Hence we should add an additional component ie the entrainer, which can first break the existing azeotrope and make one of the components of the azeotrope more volatile than the other. In other words, azeotropic distillation is the process of converting a binary azeotrope into a ternary azeotrope by the addition of an entrainer.
An entrainer is a substance that we introduce to an azeotropic mixture to break it by changing the molecular interactions and creating a new azeotrope with a different composition and boiling point. The characteristics of the azeotropic mixture that undergoes separation determine the appropriate entrainer. The entrainer should be easily separable from the other components of the azeotropic mixture and form a new azeotrope with one of them.
The entrainer can change the activity coefficient of different compounds in different ways when added to the liquid phase, changing the relative volatility of a mixture. Greater deviations from Raoult’s law make it simpler to add another component and create considerable changes in relative volatility. In azeotropic distillation, the additional component has the same volatility as the mixture and one or more of the components combine to generate a new azeotrope due to polarity differences.
The most common types of entrainers in azeotropic distillation include:
Extractive entrainers
Azeotropic entrainers
Extractive Entrainers
Extractive entrainers are substances having a higher boiling point than the initial mixture and combining with one of the components in the azeotropic mixture to generate a new azeotrope. The mixture is heated after the addition of the extractive entrainer.
The extractive entrainer combines one of the original mixture’s components to create a new azeotrope as the mixture’s temperature rises. We can distill out the new azeotrope from the original mixture since it has a higher boiling point than the latter. A further distillation separates the entrainer from the isolated component.
Azeotropic Entrainers
Azeotropic entrainers are substances having a lower boiling point than the initial mixture and produces a new low boiling azeotrope. The most well-known example is the water – ethanol azeotrope when benzene or cyclohexane is added. The ternary azeotrope, which is 7% water, 17% ethanol, and 76% cyclohexane, boils at 62.1 °C with cyclohexane acting as the entrainer. The water/ethanol azeotrope is given just enough cyclohexane to engage all of the water in the ternary azeotrope. The azeotrope ( Benzene – water ) vaporises when the combination is then heated, leaving a residue that is almost entirely made up of ethanol.
Molecular Sieves
A common approach involves the use of molecular sieves. Treatment of 96% ethanol with molecular sieves gives anhydrous alcohol, the sieves having adsorbed water from the mixture. The sieves can be subsequently regenerated by dehydration using a vacuum oven.
Shall we wrap up?
Conclusion
In this blog, we had a short discussion on azeotropes, their formation, properties and the methods of separating them. Azeotropic distillation, pressure swing distillation and molecular sieves are some of the existing methods available. In case of any doubts, please feel free to ask in the comments section. Happy Learning!
Types of beams popularly used In construction and engineering are classified based on their shape, the way they are supported, their structural behaviour etc. The beam is a horizontal or sloping structural member that supports a load and resists bending. Beams are typically made from materials such as wood, steel, or concrete, and are used to support floors, roofs, and walls, as well as to bridge gaps between supports. The type of beam used depends on factors such as the load to be supported, the span length, and the structural design of the building or structure. Beams can come in a variety of shapes, including rectangular, square, circular, and I-shaped. Proper selection and installation of beams are critical for ensuring the stability, safety, and durability of a structure.
This article is about the different types of beams popularly used in civil engineering and construction.
Types of Beams can be classified based on several factors, including their shape, the way they are supported, and their structural behaviour. Here are some common classifications of beams:
Beams can be classified as rectangular, square, circular, I-shaped (also known as H-beam), T-shaped, and L-shaped.
Types of beams Based on support conditions
Beams can be classified as simply supported, fixed, cantilever, continuous, and overhanging.
Types of beams Based on structural behaviour
Beams can be classified as determinate or indeterminate. Determinate beams have a fixed number of supports and can be analysed using statics. Indeterminate beams have more supports than are needed for stability and require more advanced analysis techniques to determine their behaviour.
Types of beams Based on the material
Beams can also be classified based on the material used, such as wood, steel, or concrete.
The choice of beam type depends on the load to be supported, the span length, and the structural design of the building or structure.
Types of beams based on the shape
Beams can be classified based on their shape, which refers to the cross-sectional profile of the beam. The shape of the beam affects its structural properties, such as its strength, stiffness, and weight. Here are some common shapes of beams.
Rectangular beam
A rectangular beam is a type of beam that has a rectangular cross-section. It is a simple and commonly used beam in construction due to its ease of fabrication and ability to support both bending and compression loads. Rectangular beams are typically made from materials such as wood, steel, or concrete.
Square beam
A square beam is a type of beam that has a square cross-section. It is commonly used in applications where a symmetric load is expected, and it provides uniform support in all directions. Square beams are typically made from materials such as wood, steel, or aluminium and are used in construction, manufacturing, and other engineering applications.
Circular beam
A circular beam is a type of beam that has a circular cross-section. It is commonly used in applications where torsion is a concern, such as in helicopter blades and wind turbines. Circular beams provide strength and stability in all directions and are typically made from materials such as steel, aluminium, or composite materials.
I-shaped (H-beam)
An I-shaped beam, also known as an H-beam, is a type of beam that has an I-shaped cross-section. It is commonly used in construction because of its high strength-to-weight ratio and ability to support large loads. I-shaped beams are typically made from steel. They are used in a variety of applications, such as bridges, buildings, and other infrastructure.
T-shaped beam
A T-shaped beam is a type of beam that has a T-shaped cross-section. It is commonly used as a lintel or in other load-bearing applications where a shallow beam is needed. T-shaped beams provide structural support in one direction. They are typically made from materials such as steel, wood, or reinforced concrete.
L-shaped beam
An L-shaped beam is a type of beam that has an L-shaped cross-section. It is commonly used as a bracket or in other applications where load-bearing support is needed. L-shaped beams provide structural support in two directions and are typically made from materials such as steel, wood, or reinforced concrete.
The choice of beam shape depends on the load to be supported, the span length, and the structural design of the building or structure.
Types of beams based on support conditions
Beams can also be classified based on their support conditions, which refers to how the beam is held in place. Here are some common support conditions for beams:
Simply supported beams
A simply supported beam is a type of beam that is supported at both ends and is free to rotate. It is one of the most common support conditions for beams and is used in a wide range of applications, such as bridges, buildings, and other infrastructure. Simply supported beams are typically used to support lighter loads and have a simple design.
Fixed beams
A fixed beam is a type of beam that is rigidly fixed at both ends and cannot rotate. This support condition results in a beam that is capable of supporting heavier loads than a simply supported beam. Fixed beams are commonly used in construction, such as in the construction of tall buildings or other structures that require a high level of load-bearing capacity. However, the design of fixed beams is more complex than simply supported beams due to the structural constraints imposed by the fixed supports.
Cantilever beams
A cantilever beam is a type of beam that is supported at one end and is free to rotate at the other end. It is commonly used in applications where an overhanging structure is required, such as in balconies or bridges. Cantilever beams are capable of supporting relatively heavy loads and have a unique design that requires careful consideration of the forces acting on the beam.
Continuous beams
A continuous beam is a type of beam that is supported by more than two supports and has one or more internal supports. This support condition results in a beam that is capable of supporting heavier loads than a simply supported beam or cantilever beam. Continuous beams are commonly used in construction, such as in the construction of bridges or multi-story buildings, and require careful consideration of the distribution of loads and internal support points.
Overhanging beam
An overhanging beam is a type of beam that extends beyond its supports and has one or more overhanging sections. This support condition results in a beam that is capable of supporting loads that are not symmetrical or evenly distributed. Overhanging beams are commonly used in construction, such as in the construction of balconies or awnings, and require careful consideration of the distribution of loads and the structural design of the overhanging section.
The choice of support condition depends on the load to be supported, the span length, and the structural design of the building or structure. Different support conditions result in different load-bearing capabilities and structural behaviour for the beam, which must be taken into account during the design process.
Types of beams based on structural behaviour
Beams can be classified as determinate or indeterminate. Determinate beams have a fixed number of supports and can be analyzed using statics. Indeterminate beams have more supports than are needed for stability and require more advanced analysis techniques to determine their behaviour.
Types of beams based on materials used
Beams can also be classified based on the materials used in their construction. Here are some common classifications based on materials:
Timber beam
A timber beam is a type of beam that is made from wood. Timber beams are commonly used in residential and light commercial construction due to their relatively low cost, ease of construction, and natural aesthetic appeal. However, their strength and durability can be limited compared to other materials, which must be taken into account during design.
Steel beam
A steel beam is a structural element made of steel that is used to support loads over a span. It is typically I-shaped or H-shaped and comes in various sizes and lengths. Steel beams are commonly used in construction projects such as bridges, buildings, and infrastructure due to their strength and durability.
Concrete beam
A concrete beam is a structural element made of reinforced concrete that is used to support loads over a span. It is typically rectangular or T-shaped and comes in various sizes and lengths. Concrete beams are commonly used in construction projects such as buildings, bridges, and infrastructure due to their strength and durability.
Composite beam
A composite beam is a structural element made of a combination of different materials, typically steel and concrete, that work together to support loads over a span. The steel and concrete are bonded together to create a strong, durable beam that can be used in construction projects such as buildings, bridges, and infrastructure.
The choice of material depends on the load to be supported, span length, and other design requirements. Each type of beam has unique structural properties that must be taken into account during the design process to ensure that the beam can support the intended loads.
Types of Cement used in construction are categorised according to their properties, applications, and advantages. Concrete construction involves the use of different varieties of cement, each possessing unique characteristics, benefits, and applications that depend on the materials utilized in their production. This categorization is based on the composition of the materials used in production.
Cement is an integral part of all types of construction ranging from huge skyscrapers, bridges, tunnels, etc to small residential buildings. It is one of the oldest and most used binding materials and an integral ingredient used in the construction sector. There are different types of cement available in the market. Each type of cement has its application depending on its properties. This article is about the cement types mostly used in construction.
15 Types of Cement and Their Uses
Let us have a look at the top 15 cement types widely used in India and other nations. They are,
Ordinary Portland cement
Portland pozzolona cement
Portland Slag cement
Rapid hardening cement
Hydrophobic Portland cement
Low-heat Portland cement
Sulphates resisting Portland cement
Quick setting Cement
High alumina cement
Masonry cement
White cement
Coloured cement
Expansive cement
Air-entraining Portland cement
Hydrographic cement
Ordinary Portland cement (OPC ) – Types of Cement
OPC stands for Ordinary Portland Cement, which is one of the most commonly used types of cement in construction. It is made from a mixture of limestone, clay, and other materials, heated at high temperatures to produce a fine powder. Mostly, gypsum, calcareous material, and argillaceous substance make up Ordinary Portland Cement. OPC cement has excellent binding properties and provides high compressive strength to the concrete.
Ordinary Portland Cement is versatile and suitable for a wide range of construction applications, including buildings, bridges, and pavements. Ordinary Portland Cement is available in different grades, each with unique characteristics, making it easy to choose the most appropriate type for a specific construction project. Additionally, it has a relatively fast setting time, allowing for faster completion of construction projects. Ordinary Portland cement is more economical and forms a crucial component of high-strength concrete. This kind of cement is well-resistant to deterioration from chemicals, shrinkage, and fractures.
Portland pozzolana cement – Types of cement in India
Portland Pozzolana Cement (PPC) is a type of cement made by combining Portland cement clinker with pozzolanic materials like fly ash, volcanic ash, or silica fumes. contains 15% to 35% pozzolanic ingredients, gypsum, and clinker. The pozzolanic materials improve the workability and durability of concrete and reduce the risk of cracking. PPC is preferred in locations with high moisture content, as it is highly resistant to dampness and corrosion. It is also eco-friendly since it uses industrial waste as a raw material. PPC cement is suitable for a wide range of construction applications, including dams, bridges, and buildings.
PPC has an initial setup time of 30 minutes and an ultimate setting time of 600 minutes. It is appropriate for hydraulic and marine structures. sewage works, and underwater concrete laying, such as bridges, piers, dams, and mass concrete works. because PPC has strong resistance to sulphate attack. PPC has a slower setting time than OPC, which may prolong construction time. Its initial strength is also lower than OPC.
Portland Slag Cement (PSC) -Types of cement for concrete
Portland Slag Cement (PSC) is a type of cement made by blending granulated blast furnace slag (GGBFS) with Portland cement clinker. The slag is a waste product from steel manufacturing, making PSC an eco-friendly alternative to traditional cement. PSC has excellent workability, durability, and low heat of hydration. It is widely used in construction applications such as dams, bridges, and underground structures. PSC provides high strength and durability, making it a popular choice for high-performance concrete. It is also known for its resistance to chloride and sulphate attacks. It has good compressive strength.
Rapid hardening cement – Types of cement in India
Rapid Hardening Cement (RHC) is a type of cement that attains high strength in a short time. It is made by grinding Portland cement clinker with a higher amount of C3S and a lower amount of C2S. RHC is suitable for emergency repair works and precast concrete components. Its rapid setting and strength gain properties make it ideal for use in cold weather conditions. It has high resistance to chemical attacks. RHC needs less curing time. The strength of rapid hardening cement at the three days is similar to the 7 days strength of OPC with the same water-cement ratio. So it is suitable for formworks, pavements etc. It has more application than OPC because of its early hardening property. Rapid-hardening cement is expensive.
Hydrophobic Portland cement
Hydrophobic Portland Cement (HPC) is a type of cement that repels water due to its chemical composition. It is made by adding water-repellent chemicals to the cement during the grinding process. HPC is suitable for construction projects in areas with high rainfall or moisture content. It is commonly used in the construction of basements, swimming pools, and water storage tanks. HPC also has increased durability and can resist chemical attacks. It consists of admixtures such as acid naphthene soap, oxidized petrolatum, etc., reducing the melting of cement grains. The strength of hydrophobic cement is similar to OPC after 28 days. This type of cement is expensive.
Low-heat Portland cement
Low-heat Portland cement is a type of cement that produces less heat during hydration, which reduces the risk of cracking and improves durability. It is typically used in large concrete structures such as dams, bridges, and high-rise buildings, as well as in mass concrete applications. Because the heat of hydration of this type of cement is 20% less than normal cement. It consists of 5% of tricalcium aluminate and 46% of dicalcium silicate. Therefore it produces low heat of hydration. It has excellent wear, impact resistance and workability.
Sulphate-resisting Portland cement
Sulphate-resisting Portland cement (SRPC) is a type of cement designed to resist the effects of sulphates, which can cause concrete to deteriorate. It contains lower levels of tricalcium aluminate, which is the component most susceptible to sulphate attack. SRPC is commonly used in construction projects involving soil with high sulphate content or exposure to seawater.
Quick setting Cement
Quick-setting cement is a type of cement that hardens and gains strength rapidly after mixing with water, usually within 5 to 30 minutes. It is used in situations where the rapid setting is necessary, such as in cold weather or for emergency repairs. However, quick-setting cement may not be suitable for projects requiring longer workability or for structures that need to withstand heavy loads over time. It is a special type of cement manufactured by adding aluminium sulphate and reducing the amount of gypsum. It is applicable for underwater concreting and grouting. The setting time of this cement is less because aluminium sulphate is an accelerating admixture. It is also preferable for concrete repair works, tunnelling etc.
High alumina cement
High alumina cement (HAC) is a type of cement that is made from bauxite and limestone with a high percentage of alumina content, typically over 35%. It sets and hardens rapidly, has high early strength, and can withstand high temperatures and acidic environments. It is commonly used in refractory applications such as furnace linings, precast shapes, and high-temperature concretes. However, HAC is not recommended for structural applications due to its high shrinkage and susceptibility to chemical attacks over time. High alumina concrete attains strength within 24 hours. It can withstand high temperatures and fire. It is applicable in refractory concrete. Rapid hardening cement with an initial and final setting time of about 3.5 and 5 hours, respectively.
Masonry cement
Masonry cement is a type of cement that is specifically designed for use in masonry construction, such as bricklaying and plastering. It is a blend of Portland cement, hydrated lime, and sometimes additional additives such as sand, clay, or other minerals. The addition of hydrated lime improves the workability and durability of the cement, and it also enhances the bond strength between the cement and the masonry units. Masonry cement is commonly used in both exterior and interior masonry applications, such as building walls, chimneys, and decorative stonework. Since it has low strength it is not suitable for structural applications. The cost of masonry cement is less. Also, they have high water retentivity and workability.
White cement
White cement is a type of cement that is similar to Portland cement, but with a white or light-coloured appearance. It is made from raw materials with low iron content, such as limestone, kaolin, and clay, and is often used for decorative or architectural purposes, such as in terrazzo flooring, precast panels, and ornamental concrete. White cement is also used in applications where colour consistency is important, such as in coloured concrete or mortars, as it can be tinted to various shades. It has similar properties to grey cement in terms of setting time, strength development, and durability. White cement is manufactured by using limestone, clay, oil and gypsum. But they are expensive compared to normal cement.
Coloured cement
Coloured cement is a type of cement that is produced by adding pigments to the raw materials during the manufacturing process. It is available in a wide range of colours, and the pigments used can be natural or synthetic. Coloured cement is used in decorative concrete applications where aesthetics are important, such as stamped concrete, exposed aggregate, and decorative overlays. It can also be used in architectural concrete, including precast panels, masonry units, and concrete countertops. The colour of the cement can be affected by the curing process, and it is important to use a consistent curing method to ensure the desired colour is achieved. Coloured cement consists of colour pigments like chromium, cobalt, ton oxide, manganese oxide etc which gives them colour. It is preferable for floor finishing, window sills stair treads, and other external surfaces. The number of colouring pigments should about be 5 to 10 per cent.
Coloured cement
Expansive cement
Expansive cement is a type of cement that expands during the early stages of hydration. It contains a mixture of Portland cement clinker, gypsum, and an expansive agent, such as calcium sulphate or anhydrite. Expansive cement can expand up to 3% of its original volume, and this expansion can help offset the shrinkage that occurs as the concrete dries and hardens, reducing the risk of cracking. It is commonly used in applications where shrinkage cracking is a concern, such as in large concrete structures, pavements, and bridge decks. However, the expansion can also cause problems if it is not properly controlled, and it is important to follow the manufacturer’s guidelines for use.
K-type expansive cement
M-type expansive cement
S-type expansive cement
The use of expansive cement is in water retaining structures, concrete repairing, large floor slabs, etc.
Air-entraining Portland cement
Air-entraining Portland cement is a type of cement that contains an air-entraining agent, such as resins, surfactants, or fatty acids, that creates microscopic air bubbles in the concrete. These air bubbles improve the durability of the concrete by reducing the effects of freeze-thaw cycles, as the water trapped in the bubbles can expand and contract without damaging the concrete. Air-entraining Portland cement is commonly used in cold climates or areas with high humidity, where freeze-thaw cycles can cause damage to concrete structures. However, the use of air-entraining agents can also reduce the compressive strength of the concrete, so it is important to properly balance the amount of air entrainment with the desired strength and workability of the concrete. Air-entraining agents like aluminium powder and hydrogen peroxide are added to the cement.
Hydrographic cement
Hydrographic cement, also known as underwater cement, is a type of cement that can harden and set even when submerged in water. It is specifically designed for use in underwater construction projects, such as building foundations, bridges, and pipelines. Hydrographic cement contains special additives that allow it to set and harden underwater without being affected by the water, and it can also be mixed with accelerators to speed up the setting time. The cement is typically mixed and applied using specialized equipment, such as pumps or tremies, to ensure proper placement and consolidation.
The Graduate Aptitude Test in Engineering (GATE) is one of the most prestigious national-level entrance exams in India. Every year, the exam is conducted by the Indian Institute of Science (IISc) and seven Indian Institutes of Technology (IITs) on a rotational basis. The GATE exam tests the aptitude of engineering and science graduates aspiring for higher education and jobs in the field of engineering, technology, and research. In this article, we will discuss the GATE CE Exam Notification 2024, including the exam date, application process, syllabus, eligibility criteria, and result.
The GATE exam is a computer-based test conducted for 27 papers, including Civil Engineering (CE). The GATE CE exam tests the candidates’ understanding of various topics related to civil engineering, such as Structural Engineering, Geotechnical Engineering, Water Resources Engineering, Environmental Engineering, Transportation Engineering, and Construction Management.
GATE CE Exam Notification 2024
The GATE CE Exam Notification 2024 was released on August 10, 2023, by the Indian Institute of Science (IISc). The official website for GATE 2024 is gate.iisc.ac.in. The notification includes all the important details about the exam, such as exam date, schedule, eligibility criteria, syllabus, the application process, exam pattern, admit card, exam centers, result, scorecard, and cut off.
Eligibility Criteria
The eligibility criteria for the GATE CE exam are as follows:
The candidate must have a Bachelor’s degree in Engineering/Technology/Architecture or Master’s degree in any relevant Science subject.
The candidates appearing in the final year of their qualifying exam are also eligible to apply.
There is no age limit to appear for the GATE exam.
Exam Date and Schedule
The GATE CE exam is scheduled to be held on February 3, 4, 10, and 11, 2024. The exam will be conducted in two sessions, i.e., the forenoon session from 9:00 am to 12:00 pm and the afternoon session from 2:00 pm to 5:00 pm.
Application Process
The application process for the GATE CE exam is entirely online. The candidates can apply for the exam by visiting the official website gate.iisc.ac.in. The application fee for the GATE exam is Rs. 1500 for General/OBC candidates and Rs. 750 for SC/ST/PwD candidates. The last date to apply for the exam is September 15, 2023.
Exam Pattern and Syllabus
The GATE CE exam consists of 65 questions for a total of 100 marks. The exam is divided into two sections, i.e., General Aptitude (15 marks) and Technical (85 marks). The Technical section consists of two types of questions, i.e., Multiple Choice Questions (MCQs) and Numerical Answer Type (NAT) questions.
The syllabus for the GATE CE exam is divided into seven broad sections, i.e., Engineering Mathematics, Structural Engineering, Geotechnical Engineering, Water Resources Engineering, Environmental Engineering, Transportation Engineering, and Construction Management. Each section has several topics, and the detailed syllabus is available on the official website.
Admit Card and Exam Centers
The GATE CE exam admit card will be available for download on the official website. Candidates need to download and take a printout of the admit card and carry it to the examination center along with a valid photo identity proof.
The exam centers for the GATE CE exam will be spread across multiple cities in India and a few international cities. Candidates can choose up to three exam centers in order of preference during the application process. The exam conducting authority will allocate the exam center based on availability and feasibility.
Result and Scorecard
The result of the GATE CE exam 2024 has been declared on March 30, 2024, on the official website. Candidates can download their scorecard from the same website from April 1, 2024, onwards. The scorecard will contain the candidate’s name, registration number, marks obtained, and the All India Rank (AIR). The GATE score is valid for three years from the date of declaration of the result.
Cut-Off Marks and Qualifying Criteria
The GATE CE exam cut-off marks are the minimum marks that candidates need to obtain in order to qualify for the exam. The cut-off marks vary every year based on factors such as the difficulty level of the exam and the number of candidates appearing for the exam. The qualifying criteria for the GATE CE exam is that the candidate should obtain a minimum of 25 marks out of 100.
Counselling and Admission Process
The GATE CE exam score is accepted by several institutes and universities in India for admission to postgraduate courses in Civil Engineering and related fields. The counselling and admission process varies for different institutes and universities. Candidates need to apply separately to the institutes or universities of their choice and go through the respective counselling and admission processes.
GATE CE Exam Online Coaching
If you’re aspiring to crack the GATE CE exam, then opting for GATE CE online coaching can be a game-changer for you. With the convenience of learning from anywhere and anytime, online coaching offers a plethora of benefits to students. Not only do you get access to expert faculty members, but also high-quality study material and mock tests that are crucial for exam preparation. Additionally, online coaching also saves you the time and effort of commuting to a physical classroom, allowing you to utilize that time for self-study and revision. So, enrol in a reliable GATE CE exam online coaching program today, and give yourself the best chance of acing the exam.
Conclusion
The GATE CE exam is an important examination for aspiring Civil Engineers. It provides a platform for candidates to showcase their knowledge and skills in the field of Civil Engineering and helps them to get admission to some of the most reputed institutes and universities in India. Candidates should prepare well for the exam by following the exam pattern and syllabus, practising the previous year’s question papers, and taking mock tests. They should also keep themselves updated with the latest exam notifications and announcements.
Flushing door or flush doors are internal doors with a basic and elegant form, a level surface, and minimum decoration. The door panels are flush with the frame, hence the name “flush door.” Flush doors are popular in modern architectural design because of their clean, minimalist appearance and adaptability.
Doors obstruct or provide access to an entrance or exit to a building, room, or vehicle. Doors are essential for providing security and privacy. They can be made of various materials, including wood, metal, glass, or composites. They come in different forms. Doors are outfitted with a range of hardware such as locks, handles, hinges, and closers. This is to limit access and facilitate smooth operation. The type of door and hardware used depends on the intended purpose and location. For example, residential doors are typically more aesthetically pleasing, while commercial doors prioritize functionality and durability. Doors are essential in building construction and architecture because they can contribute to the overall aesthetics of a room.
This article is about Flush doors and types of flush doors used in building construction and architecture.
What is a flushing door or flush door?
A flush door is an interior door with a smooth, flat surface and no decoration or raised panels. The door panels are flush with the frame, giving the door its name. These doors have a wooden frame with plywood, MDF, or natural wood fixed on both sides. The top surface is finished with laminated sheets, veneers, paint, etc., resulting in a standardized and straightforward appearance. Flush doors are commonly constructed using wood in residential buildings due to their attractive and rich appearance. Poplar, mango, or pine wood can be used to construct the doors.
Flush doors are classified into different types. Classification is based on the materials used, the manufacturing method, the finish, and the location of the application.
The following are a few examples of common flush door designs:
Solid Core Flush Doors
Hollow Core Flush Doors
Cellular core flush door
Fire-rated flush door
Louvered flush door
Acoustic flush door
Let us discuss different types of flush doors in detail
Solid Core flushing/flush Doors
The manufacturers sandwich a solid core between two thin sheets of plywood or MDF. The core is made of particleboard, MDF, or solid wood. This construction provides a flush surface on both sides of the door. They then veneer the door with real wood or decorative laminate. These doors typically consist of robust and mineral-based timber and use a variety of materials. The materials they use include blockboard, laminated core, cross band, face wood veneer, and particle board.
This construction method improves the door’s durability and resistance to damage compared to a hollow core door. Solid-core flush doors find frequent use in both residential and commercial structures. This is because of their excellent sound insulation and privacy features.
Solid-core flush doors are popular due to their customization options and affordability compared to solid wood doors. Solid core flush doors come in various sizes and styles, including panel and slab options. They can also be purchased with a range of hardware options, including hinges, handles, and locks.
Cellular core flush door
The cellular core flush door comprises a hollow core made up of a honeycomb or grid-like structure. The core is then sandwiched between two thin sheets of plywood or MDF. This creates a flush surface on both sides of the door. This construction method creates a lightweight and cost-effective door that is still relatively sturdy and durable.
The core of cellular core flush doors generally consists of a honeycomb or grid-like structure. The materials used to construct the core include cardboard or engineered wood, such as particleboard, MDF, or plywood. This structure creates a strong, yet lightweight core. The core provides some insulation and sound dampening, although not as much as a solid core door.
Cellular core flush doors are popular in residential and commercial buildings. This is because they are relatively affordable, lightweight, and easy to install. Manufacturers offer a variety of sizes and styles for cellular core flush doors, such as panel and slab designs. Additionally, these doors are painted or stained to match any interior decor.
Doors made with this construction method may not offer the same level of durability or sound insulation as solid-core flush doors. This makes them more susceptible to damage from impacts or moisture. As a result, they are mainly used for interior residential doors rather than high-traffic commercial or industrial settings.
Hollow core flush door
Two thin sheets of plywood or MDF sandwich a lattice or grid-like structure to create a flush surface on both sides of hollow core flush doors, which are a type of interior door with a hollow core. The hollow core makes the door lightweight and easy to handle. This makes them a popular choice for interior doors in residential and commercial settings.
Hollow core flush doors are relatively affordable, and they are available in a variety of sizes and styles, including panel and slab designs. They are also easy to install, and they can be painted or stained to match any interior decor.
While hollow-core flush doors are lightweight and affordable, they do have some limitations. They are not as durable or sound-insulating as solid core or cellular core flush doors. The hollow core can also make them more prone to damage from impacts or moisture. Hollow core flush doors have a lattice or grid-like structure sandwiched between thin plywood or MDF sheets, making them best suited for interior use where sound insulation and durability are not a significant concern.
Fire-rated flush Door
Fire-rated flushing/flush doors withstand fire and smoke for a certain period of time. People typically use them in commercial or public buildings, as well as in multi-family residential buildings where building codes require their installation in areas that require fire resistance.
Manufacturers typically make fire-rated flush doors from fire-resistant materials, including metal, gypsum, or solid core materials like particleboard, MDF, or timber. The doors are often filled with fire-resistant materials Further they are covered with a layer of fire-resistant material, such as sheet metal, gypsum, or special fire-resistant paint.
The rating of a fire-rated flushing door is determined by the length of time it can withstand a fire before it begins to fail. Fire ratings typically range from 20 minutes to 3 hours or more, and the required rating will depend on the building code and the specific application.
Fire-rated flushing doors may also have additional features, such as intumescent strips around the edges or fire-resistant glazing, to help contain fire and smoke. These doors can also be equipped with special hardware, such as self-closing hinges and automatic door closers, to help ensure that the door remains closed during a fire.
Ensuring the correct installation of fire-rated flush doors in accordance with local building codes is crucial to guarantee the required level of protection in case of a fire.
Louvered Flushing Door
A louvred flushing door is a type of interior door that has a series of horizontal slats or louvres inserted into the door panel. The manufacturers can make the louvres from wood, glass, or metal, and they usually fix them in place. However, some designs may permit adjustable louvres.
Louvred flush doors find their usage in areas that require air circulation or ventilation, such as utility rooms or closets. They can also be used in rooms that need privacy or light control, such as bathrooms or bedrooms.
The design of a louvred flush door can vary widely, from traditional styles with solid wood louvres to more modern designs that incorporate metal or glass louvres. They are also available in a variety of sizes and configurations, including single or double doors, and with different hardware options, such as hinges and handles.
Manufacturers can make louvred flush doors from various materials, such as wood, MDF, or metal, and they can paint or stain them to match any interior decor. They can also paint or finish the louvres in different colours or textures to add an extra design element to the door.
Overall, louvred flush doors provide a unique combination of ventilation, privacy, and design that make them a popular choice for a variety of applications in residential and commercial buildings.
Acoustic flushing door
People often use acoustic flush doors in commercial settings such as recording studios, theatres, and conference rooms where privacy and sound isolation are important. The manufacturer selects materials with soundproofing properties to construct an acoustic flush door, and they usually build it with a solid core that dampens sound waves.
The name “flush” door comes from its design, which allows it to fit within the plane of the surrounding wall, creating a smooth and seamless surface when closed. This helps to prevent sound from leaking through gaps around the edges of the door.
People often use acoustic flush doors in commercial settings, such as recording studios, theatres, and conference rooms, where they require privacy and sound isolation. Homeowners can also use acoustic flush doors in residential settings, particularly in homes with open floor plans or in rooms where noise levels need to be controlled, such as home theatres or bedrooms.
When selecting an acoustic flush door, it is essential to consider factors such as the sound transmission class (STC) rating, which indicates the door’s ability to block sound, as well as the material used for the door’s core and surface. Proper installation and sealing of the door are also crucial for optimal soundproofing performance.
Driven piles support structures and transmit loads to underlying soil or rock, as they are a type of deep foundation used for this purpose. Contractors use driven piles, made of steel, concrete, or wood, to support structures and transmit loads to underlying soil or rock. They also call them displacement piles. The installation of driven piles involves driving them into the ground using impact hammers or vibratory drives until they reach a layer of rock or soil that can support the required loads.
If the soil is exceptionally dense, they may need to pre-drill to ensure the pile reaches the design depth. Construction projects commonly employ driven pile to provide stability and strength to the structure. Driven piles offer a cost-effective deep foundation solution and are commonly used to support buildings, tanks, towers, walls, and bridges.
Why driven piles?
Contractors often use driven piles, which are the most cost-effective deep foundation solution, to support buildings, tanks, towers, walls, and bridges. They are also suitable for embankments, retaining walls, bulkheads, anchorage structures, and cofferdams. Driven piles possess a high load-bearing capacity, durable, and contractors can install them quickly and effectively in various soil conditions. Engineers frequently use them in places with inadequate soil, where conventional shallow foundations would not be strong enough to sustain buildings.
In addition, contractors can install driven piles to support compression, tension, or lateral loads, with specifications determined by the structure’s needs, budget, and soil conditions, making them very versatile.
Steel-driven piles support major structures such as buildings, bridges, roads, and industrial facilities in construction. Construction workers push them into the earth using specialized tools like hydraulic hammers or pile drivers until they reach a predetermined depth or a firm layer of rock or soil. Steel-driven piles are steel beams with broad flanges on both ends.
Steel-driven piles are typically made of high-strength steel with a round or square cross-section. They come in various lengths and widths and can be installed vertically or at an angle to meet foundation design requirements. An impact hammer is used to press the pile into the soil by delivering a forceful blow. For shorter depths, steel screw piles are supported by a cast iron helix and powered by rotary motors.
Because of their durability, strength, and capacity to support enormous loads, the steel-driven pile is a common choice for deep foundations. Steel-driven piles are a cost-effective and quick solution for many construction projects. However, their applicability will depend on factors such as soil characteristics, anticipated loads, and local construction building codes and regulations.
Pre-cast concrete Driven Piles
Precast concrete pile manufacturers deploy these piles in construction to support structures built on weak or compressible soils. They prefabricate these piles in a factory or casting yard before transporting them to the construction site. Based on the project’s unique needs, they can construct precast concrete piles in a vast range of dimensions, forms, and configurations. High-strength concrete, reinforced with steel rebar, is used to make these piles. They often use a vibratory hammer or hydraulic hammer to drive the piles into the earth until they reach the required depth or a solid layer of soil or rock.
Piles come in a variety of shapes, such as square, octagonal, cylindrical, or sheet. Percussion-driven piles are used in situations where bored piles would be ineffective due to running water or excessively loose soils. They have a load range of 300-1,200 kN and a maximum reach of 30 m. Precast concrete piles are constructed with great accuracy and quality control in a controlled environment, resulting in a consistent and uniform product that satisfies design requirements. They are durable and can withstand adverse weather conditions such as seawater or chemical exposure. Precast concrete piles can also be installed quickly and effectively, saving time.
Precast concrete piles are quick to install.
They can be used in various soil conditions.
Using precast concrete piles saves time and money in construction.
Precast concrete piles are durable and reliable.
They have high-quality control standards.
Precast concrete piles are a popular choice for deep foundation construction.
Timber pile
Timber-driven piles are used in construction to create a stable foundation for structures in weak or compressible soils. Contractors use hammers or pile drivers to create cylindrical or square wood piles from premium softwood species. This type of pile is particularly effective in areas with high water tables where other types of piles may not work as well. Timber-driven piles provide a stable foundation for structures in weak or compressible soils. This is achieved by hammering wooden piles into the ground, which compresses the wood and displaces the surrounding soil. The resulting tight fit helps to support the weight of the structure. Timber-driven piles have the advantages of being inexpensive and simple to install. Nonetheless, they may be susceptible to rot and pest infestation.
timber-driven-pile
Composite driven pile
Engineers commonly use composite piles made of a combination of two or more materials, such as concrete, steel, or timber, when soil conditions require a combination of strength and flexibility. An example of a composite pile is a concrete pile with a steel section, as shown in the figure.
Contractors use composite-driven piles consisting of a steel tube filled with concrete and reinforced with steel rebar because they can withstand heavy loads. They use in various construction projects, such as bridges, high-rise buildings, and marine structures. The steel tube provides structural support and protects the concrete from damage during installation, while the concrete and rebar provide additional strength and stability. Contractors can install composite piles using hydraulic hammers or vibratory drivers to reach depths of up to 60 meters. Due to their durability and corrosion resistance, composite piles are ideal for use in harsh environments.
Quality Control for Driven Piles
The construction of driven piles requires high-quality materials and adherence to standards such as BS 8004:2015 and EC standards. It’s crucial to maintain the pile’s shape and avoid damage during installation and inspect them beforehand for quality assurance. The maximum load a pile can carry depends on soil or rock strata properties, pile dimensions and material, and installation method. Engineers perform load testing on representative samples to determine capacity and use monitoring instruments like inclinometers and settlement gauges to ensure the pile’s sufficient support. Effective quality control and testing are crucial for the safe and reliable performance of driven piles in construction projects.
During installation, it is crucial to maintain the shape of driven piles and ensure they are not damaged by the installation of subsequent piles.
Quality control of driven piles is an important aspect of ensuring the stability, safety, and longevity of structures that rely on them for support. Here are some of the common quality control measures used for the driven piles.
Pile driving equipment for driven piles
To make sure that piles are installed correctly, trained personnel are required to maintain, calibrate, and operate pile driving equipment properly. Regular inspections are necessary to detect any damage or wear in the equipment, and repairs or replacements must be made promptly.
Pile inspection and testing
Inspect the piles for defects or damage before driving them into the ground. To ensure that the piles have been installed correctly and meet the specified requirements, non-destructive testing methods such as sonic testing or integrity testing should be used to test the piles after installation.
Pile load testing for driven pile
One can conduct load testing of a sample of piles to ensure that they can support the required loads. This involves applying a controlled load to the pile and measuring the resulting deformation, which one can compare to the design specifications to ensure that the piles are safe and reliable.
Pile driving records
One should keep detailed records of the pile driving process, including the number of blows or vibrations required to drive the pile to the required depth, the penetration rate, and any other relevant information. These records are essential to monitor the quality of the installation and identify any issues that may arise during the construction process.
Regular inspections and testing are essential to identifying any issues early in the construction process and enabling prompt corrective action.
Advantages of driven piles
The main advantages are
Piles can be pre-fabricated off-site which allows for efficient installation once on-site.
High Capacity
Piles are driven deep into soil or rock. This provides high load-bearing capacity. It’s suitable for supporting heavy structures like buildings, bridges, and marine structures. The process increases the effective length of the pile, resulting in high capacity.
Ease of Installation of driven piles
Compared to other pile types like drilled shafts, the installation of a driven pile is quick and efficient. The installation process involves driving the piles into the ground using an impact hammer or a vibratory driver. This requires minimal excavation and soil removal.
Cost-effective
Other types of foundation systems can often be more expensive than driven piles, particularly when the soil conditions are favourable. The cost-effectiveness of driven piles is due to their relatively simple installation process and the availability of pre-manufactured piles, which can reduce the time and cost required for pile installation.
Minimal disturbance
The installation process of driven piles minimizes the disturbance to the surrounding area, making them suitable for use in urban or environmentally sensitive areas. The piles are driven into the ground, which reduces the amount of soil disturbance and the need for excavation.
Versatility
Driven piles are suitable for a variety of soil conditions, including soft soils, hard soils, and rock layers. They can also be made of different materials such as steel, concrete, and timber, providing a wide range of design options.
When driven into the ground, piles displace and compact the soil, resulting in increased bearing capacity. In contrast, other types of deep foundations may require soil removal, which can cause subsidence and structural problems.
Installation usually produces little spoil for removal and disposal.
Overall, driven piles offer several advantages in terms of high capacity, speed of installation, cost-effectiveness, minimal disturbance, and versatility, making them a popular choice for foundation systems in many construction projects.
However, the use of driven piles also has some disadvantages, including their relatively high cost compared to shallow foundations, the noise and vibration associated with their installation, and the potential for damage to nearby structures or utilities. Therefore, the selection of driven piles as a foundation type depends on a variety of factors, including soil conditions, load requirements, and site-specific constraints.
Disadvantages of driven piles
In the design and construction process, it is important to consider the disadvantages of driven piles, despite their many advantages. Some of the main disadvantages of driven piles are:
Noise and vibration
The installation of driven piles can generate high levels of noise and vibration. This can be a concern for nearby residents and sensitive structures. Pile driving can cause damage to nearby structures, particularly those with shallow foundations.
Limited depth
Other foundation types may be necessary if the capacity or depth required cannot be achieved with driven piles. This is because of the limitations imposed by soil or rock conditions and the driving equipment’s capacity.
Difficulty in driving through hard soil or rock
Driving piles in hard soil or rock layers can be difficult and time-consuming, which can lead to higher installation costs. Overcoming the hardness of the soil or rock may also require the use of specialized driving equipment or techniques.
Quality Control
The installation of a driven pile requires critical quality control. Poor installation can cause issues such as pile damage, pile movement, or insufficient load capacity. To ensure that the piles are installed correctly and meet the required standards, regular inspection, and testing are required. Moreover, monitoring is necessary during pile installation.
Limited environment suitability
Driven piles may have limited suitability in environmentally sensitive areas. This includes wetlands or areas with a high water table. This is due to the potential soil disturbance caused by the driving process. Moreover, the use of chemicals for the preservation or treatment of piles can have negative impacts on the environment. It is important to consider these factors and explore alternative foundation options in such areas.
Camber in roads is the slope or angle built into the road surface, typically seen on curved or sloped sections of the road. This slope is designed to provide several benefits, including improved drainage, enhanced vehicle stability, and better driver visibility. The purpose of camber on roads is to ensure safe and comfortable driving conditions for motorists.
The slope can be positive, negative, or zero, depending on the specific requirements of theroadand the expected traffic flow. The appropriate camber for a road depends on various factors, such as the type of road, its location, and the expected speed and volume of traffic. Proper design and construction of road camber can significantly improve road safety, reduce the risk of accidents, and increase the lifespan of the road surface.
Camber in roads, or road camber, refers to the slope built into the road surface, typically seen on curved or sloped sections. The road’s camber is usually indicated by the ratio 1:n or as a percentage. Proper camber design and construction are crucial to improve road safety, reduce accidents, and ensure adequate drainage and vehicle stability.
Here’s a list of the types of camber used in road design and construction:
Positive camber
Negative camber
Zero camber
Composite camber
Sloped or straight camber
Two straight-line camber
Barrel camber
Positive camber in roads
Positive camber refers to the angle of a vehicle’s wheels where the top of the tire tilts outward from the centre of the vehicle. This can provide improved stability and handle in certain driving situations, such as high-speed cornering. However, excessive positive camber can lead to uneven tire wear and decreased handling performance.
Negative camber in roads
Negative refers to the angle of a vehicle’s wheels where the top of the tire tilts inward towards the centre of the vehicle. This can provide improved grip and handling during cornering, as the tire maintains more contact with the road. However, excessive negative camber can lead to uneven tire wear and reduced straight-line stability.
Zero camber
Zero camber refers to the angle of a vehicle’s wheels where the tire is perpendicular to the ground and the wheel is vertical. This is considered the ideal angle for tire wear and handling, providing a balance between straight-line stability and cornering grip. Many production vehicles are designed with zero camber for optimal performance and safety.
Composite camber
Composite camber refers to a combination of positive and negative camber on a vehicle’s wheels. In order to achieve optimal handling and performance in specific driving situations, one can adjust the angle of each wheel independently to create a custom setup. This allows for a personalized approach to handling and can be achieved through the use of composite camber. Composite camber is a technique commonly utilized in high-performance vehicles and motorsports to attain maximum grip and control.
Sloped camber/straight camber
Sloped camber refers to a wheel angle where the tire leans towards the inside or outside of the vehicle, creating a slope. Straight camber refers to a wheel angle where the tire is vertical and perpendicular to the ground. Sloped camber is often used in motorsports to improve cornering performance, while straight camber is more common in street vehicles for better tire wear and handling.
Two straight-line camber
Two straight-line camber refers to a setup where the camber angle is set to zero for both front and rear wheels. This provides a balanced setup that promotes even tire wear and stable handling. “People commonly use two straight-line camber in street vehicles, SUVs, and pickup trucks, prioritizing comfort, safety, and longevity over high-speed cornering performance.”
Barrel camber/Parabolic camber
“In drifting and racing applications, people commonly use barrel camber to promote tire grip . This in turn improves cornering performance by adjusting the camber angle and toe settings on each wheel independently. Barrel camber is a wheel angle where the center of the tire is lower than the edges, creating a barrel-like shape.”
Road engineers provide camber to promote safe and efficient driving. They use positive camber on curves and turns to offer better stability and prevent vehicles from sliding off the road. On the other hand, they use negative camber on straight sections to enhance tire traction and lower the risk of hydroplaning in wet conditions.
Advantages of Camber on Roads
Camber provides several advantages for road safety and efficiency. “Moreover,” positive camber assists vehicles in remaining centered on the road while turning. This in turn results in decreased skidding and improved stability. Negative camber improves tire contact with the road on straight sections, increasing traction and reducing hydroplaning risk. Camber also helps to reduce tire wear by distributing the load evenly across the tire surface, promoting longer tire life. Overall, camber is a key design feature in road engineering. This helps to promote safe, efficient, and sustainable transportation for all.
Recommended Values of Camber in Road For Different Types of Road surface by IRC:
The Indian Road Congress (IRC) provides recommended values for camber in road design, based on the type of road surface. These values are as follows:
Flexible Pavement on Earth Embankment
Straight: 1.5%
Crossfall: 2.5%
Flexible Pavement on Soft Soil
Straight: 2%
Crossfall: 3.5%
Rigid Pavement on Earth Embankment
Straight: 2%
Crossfall: 3%
Rigid Pavement on Soft Soil
Straight: 2.5%
Crossfall: 4%
Bituminous Wearing Course
Straight: 1.5%
Crossfall: 2.5%
“These values provide general guidance only and depend on local conditions, traffic volume, and other factors. It is important to note that.”
Disadvantages of excessive road camber
Providing excessive road camber height can have several disadvantages. These include:
Uneven tyre wear: Excessive camber height can cause the tire to wear unevenly, leading to reduced tire life and increased maintenance costs.
Increased fuel consumption: High camber angles can increase rolling resistance and reduce fuel efficiency, leading to higher fuel consumption and greenhouse gas emissions.
Reduced braking performance: Excessive camber can reduce the contact area between the tire and the road surface, reducing braking performance and increasing stopping distances.
Reduced stability: High camber angles can reduce vehicle stability, especially at high speeds, making the vehicle more difficult to control and increasing the risk of accidents.
Uncomfortable ride: Excessive camber can cause the vehicle to ride harshly, transmitting more shocks and vibrations to the occupants, leading to discomfort and fatigue during long journeys.
Development length is an essential concept in civil engineering that refers to the length of reinforcement required to transfer the force from the steel reinforcement to the surrounding concrete. It is crucial in ensuring that the reinforcement is effectively bonded to the concrete to resist the applied forces. “The development length depends on several factors, including the diameter of the bar and the strength of the concrete. “Another factor that affects the development length is the bond strength between the steel reinforcement and the surrounding concrete.”
Properly understanding development length is essential for designing reinforced concrete structures to ensure their safety and stability. Engineers calculate the development length to ensure that the reinforcement will provide the intended strength and reinforcement to the structure. “Insufficient development length can cause the reinforcement to fail to transfer forces to the concrete effectively. This can ultimately lead to structural failure.”
What is the development length?
To develop the full tensile strength of the reinforcement, one must embed the reinforcement in concrete for a minimum length known as the development length. This is necessary to ensure that the reinforcement can resist the applied loads. This should happen without pulling out of the concrete or causing concrete failure.
Either pull-out or splitting failure modes typically control the length. In pull-out failure, the force applied to the reinforcement exceeds the pull-out strength of the concrete. This generally causes the reinforcement to pull out of the concrete. In splitting failure, the force applied to the reinforcement causes the concrete to crack and split. This can lead to the failure of the reinforcement.
This is a critical concept in reinforced concrete structures that ensures the effective transfer of forces and prevents premature failure. It is important for the safety and stability of structures and is a crucial factor in their design and construction. The main function is as follows.
Transfer of applied forces
Ensuring effective bonding of the steel reinforcement to the surrounding concrete is the purpose of the Development length in reinforced concrete structures. This allows it to transfer the applied forces to the concrete.
Prevents structural failure:
Basically, the proper bonding of the reinforcement to the concrete prevents premature failure of the structure. This could otherwise result in catastrophic consequences.
Important for design
Properly understanding Develop length is critical for designing reinforced concrete structures. Engineers must calculate the length to ensure that the reinforcement provides the intended strength and reinforcement to the structure.
Basically, an insufficient development length can lead to the reinforcement not being able to transfer the forces to the concrete effectively. However, this results in premature failure and instability.
Structural safety and stability
Generally, this is crucial for the safety and stability of reinforced concrete structures. The failure to effectively bond the reinforcement to the concrete would result in the inability to transfer the applied forces. However, this can lead to structural failure.
Factors determining Development strength
Several factors influence the required development length to fully develop the tensile strength of reinforcement in concrete, including
Reinforcement properties: The strength and diameter of the reinforcement significantly impact the required development length. Generally, high-strength reinforcement with a larger diameter will require a longer D length to develop its full strength.
Concrete properties: The strength, stiffness, and thickness of the concrete member where we place the reinforcement are crucial factors. However, a higher concrete strength requires a longer d length, while a thicker concrete section may require a shorter length.
Bond strength: The bond strength between the reinforcement and concrete is critical in determining the development length. However, the bond strength depends on various factors. This includes the surface condition of the reinforcement, the degree of deformation, and the quality of the concrete surface.
Environmental conditions: Environmental factors such as humidity, temperature, and exposure to corrosive agents can affect the bond strength between the reinforcement and concrete. In such cases, we may require a more extended development length.
Load conditions: The type, magnitude, and direction of the load applied to the reinforcement significantly influence the development length required. Generally, Higher loads require a longer D length to prevent the reinforcement from pulling out of the concrete.
Design codes and standards: Design codes and standards typically provide guidelines for determining the minimum development length required for different types of reinforcement and loading conditions. However, these guidelines may vary depending on the specific code or standard used.
Development length as per IS 456
Basically, Clause 26.2.1 of the Indian code for the design of reinforced concrete structures (IS 456:2000) provides the formula to calculate the development length of reinforcement bars in tension. Basically, we require the length of the reinforcement bar to transfer the stresses between the reinforcement and the surrounding concrete.
The formula for calculating the D length (Ld) of a reinforcement bar with a diameter of D, embedded in concrete with a grade of M, and subject to tension, is as follows:
Ld = (0.87 fy A / 4τ_bd) + (0.2 √fc) …Equation 1
where:
fy is the characteristic strength of the reinforcement in N/mm²
A is the area of the reinforcement in mm²
τ_bd is the bond stress between the reinforcement and the surrounding concrete in N/mm²
fc is the characteristic compressive strength of concrete in N/mm²
The first term in Equation 1 represents the basic development length, which is the minimum length required for the reinforcement to fully develop its strength. The second term represents the additional development length due to the curvature of the bar.
It is worth noting that the code also provides alternative methods for calculation, such as the empirical equations given in Table 5 of the code. However, Equation 1 is the most widely used method for calculating the development length in India.
It is important to note that these calculations are based on certain assumptions and simplifications, and the actual development length required may vary based on the specific design requirements and site conditions.
Development length as per IS 456 for columns, footings and beams
The dev. length of rebars is the minimum length required for the effective transfer of forces from the steel reinforcement to the surrounding concrete. However this ensures that the reinforcement is properly bonded to the concrete, preventing premature failure of the structure.
Typical section beam-column junction
Development length as per codes
The development length of a reinforcing bar, or rebar, is the minimum length of the bar that must be embedded or overlapped with concrete to ensure proper transfer of stresses between the concrete and steel. This is a critical design parameter, and it is determined based on various factors such as the strength of the rebar, the strength of the concrete, and the design requirements of the structure.
Here are the formulas as per some commonly used codes:
ACI 318-19 (American Concrete Institute)
Ld = [(φ x Fy x As) / (4 x Fc’^(0.5))] x (1.3 for deformed bars, 1.7 for plain bars)
where: Ld = development length in inches
φ = strength reduction factor (0.7 for deformed bars, 0.8 for plain bars)
Fy = yield strength of rebar in ksi
As = area of rebar in square inches
Fc’ = specified compressive strength of concrete in psi
BS 8110-1:1997 (British Standard)
Ld = [(1.2 x σst x As) / (0.87 x Fy x (1 + (200/d))^(0.5))] x (1.4 for deformed bars, 1.7 for plain bars)
where: Ld = development length in mm
σst = stress in rebar at yield in N/mm2
As = area of rebar in mm2 Fy = characteristic yield strength of rebar in N/mm2 d = diameter of rebar in mm
IS 456:2000 (Indian Standard)Ld = [(0.87 x fy x As) / (4 x τbd x fck^(0.5))] x (1.2 for deformed bars, 1.6 for plain bars)
where: Ld = development length in mm
fy = characteristic strength of rebar in N/mm2
As = area of rebar in mm2 τbd = design bond stress in N/mm2
fck = characteristic compressive strength of concrete in N/mm2
It is important to note that the development length calculation may vary based on the specific requirements of the structure, and it is recommended to consult the appropriate code for accurate and up-to-date information.
All cement price list today is the most important update every construction engineer and civil engineering construction firm should be familiar with. Cement is the most significant and widely used construction material which forms an integral part of any structure. Cement is the major ingredient of concrete and mortar and the structural stability and life of a structure or building depend on the cement quality.
Cement is widely available on the market. Therefore, one needs to be aware of cement’s pricing before purchasing. Cement accounts for almost 20% of total construction costs. Cement is therefore one of the most expensive construction materials. One must therefore be familiar with the most recent cement price list rates that are offered on the market. Generally, cement is utilised for everything from a building’s foundation to its final touches. Because cement prices play such a significant effect on construction costs, it is necessary to consider them when making purchases.
Also, the price of each cement varies according to its quality. Yet, different types of cement are utilised in different locations. The following variables influence cement pricing:
Costs of Raw Materials: The basic raw materials for cement manufacture are limestone and clay, and their prices might fluctuate based on supply and demand situations in their respective markets.
Energy Costs: The cost of energy, such as the price of fuel and electricity, can impact cement’s cost.
Transportation Costs: The expense involved in transporting raw materials to the manufacturing plant, as well as the cost of delivering the final product to market, can influence cement prices.
Production Costs: The cost of production can be influenced by factors such as the cost of labour, the efficiency of the manufacturing process, and the level of competition in the market.
Government Regulations: Government rules, such as taxes, import duties, and environmental regulations, can also have an impact on the price of cement.
Economic Factors: Generally, economic factors such as inflation, exchange rates, and overall economic growth can all have an impact on cement prices.
Market Demand: The level of demand for cement in a particular market can also impact its price. However, during periods of high demand, prices may be higher, while during periods of low demand, prices may be lower.
Competition: The level of competition in the cement market can also influence prices. If there is a high level of competition, companies may be pressured to lower their prices in order to remain competitive.
Cement is an essential element in the construction industry. It is needed to make concrete and mortar. Cement is manufactured by heating a mixture of limestone and clay to form a powder. The powder, when mixed with water, makes a paste that sets and hardens. Some of the most common applications for cement are:
Masonry work: For laying bricks and stone, cement is used as binding material
Plastering: Cement is widely used in the production of plaster. Plaster is used to coat the interior and exterior walls and ceilings of buildings.
Cement can be used as a base material in the manufacture of floor screeds, terrazzo, and other flooring products.
Dams: It is used in the production of concrete for dams, which are structures designed to retain water.
Pipelines: Other subsurface constructions, including pipelines, are made of cement.
In summary, cement is an essential material in the construction industry and is used for a wide range of purposes, from building construction to flooring, and from masonry work to making pipes.
Top cement companies of India with the latest price list
Here is a list of the top cement companies in India along with their latest price list:
UltraTech Cement Ltd. – UltraTech Cement is the largest manufacturer of cement in India and one of the world’s leading suppliers of cement and clinker. As of February 2023, the latest price of UltraTech Cement is Rs. 350 – 400 per bag
Ambuja Cements Ltd. – Ambuja Cements is one of the leading cement companies in India. Ambuja cement is best known for its sustainable practices and use of advanced technology. As of February 2023, the latest price of Ambuja Cement is Rs. 330 -400 per bag
ACC Ltd. – ACC is one of the largest cement companies in India. ACC has a strong presence in the country’s western and southern regions. As of February 2023, the latest price of ACC Cement is Rs. 330 to 450 kg bag.
Shree Cement Ltd. – Shree Cement is a leading cement company in India. We know that Shree cement is known for its high-quality products and innovative business practices. As of February 2023, the latest price of Shree Cement is Rs. 300 – 375 per 50 kg bag.
Please note that these prices may vary based on location and market conditions.
Conclusion
Cement prices play an important part in the cost of every structure. Everyone related to the civil engineering and the construction industry should be familiar with cement prices. Hence it is required to be updated with cement prices regularly. Top brands are available in almost every part of the country.
A sheet pile is a type of driven pile that uses sections of sheet materials with interlocking edges. We generally install Sheet piles for lateral earth retention, excavation support, and shoreline protection operations. They are typically made of steel, but can also be made of vinyl, wood, or aluminium. Sheet piles are installed in sequence to the design depth along the excavation perimeter or seawall alignment. The interlocking sheet piles provide a wall for permanent or temporary lateral earth support with little groundwater inflow. We use Anchors strategically to provide lateral support Anchors.
We frequently use Sheet piles for seawalls, retaining walls, land reclamation, and underground constructions. Underground constructions include parking garages, and basements, in marine locations for riverbank protection, seawalls, cofferdams, and so on.
Sheet piles can be temporary or permanent. Permanent steel sheet pile design demands a long service life. Often we install Sheet piles using vibratory hammers. If the earth is too hard or dense, we perform the installation with an impact hammer. Hot-rolling and cold-forming are the two major methods for creating sheet piles. Manufacturing of Hot rolled piles takes place at high temperatures, and the interlocks appear to be stronger and more durable.
We install Sheet piles by driving them into the ground with an impact hammer or vibratory driver and connect them to one another by a number of interlocking mechanisms. This includes tongue-and-groove, hook-and-grip, and clutch-bolt connections. Sheet piles, once erected, form a continuous barrier that resists lateral pressure from soil or water, avoiding soil erosion, landslides, and other soil failures.
Sheet piles – Applications
Piles find frequent utilisation in the following construction projects:
Retaining walls
Sheet piles help to construct retaining walls that hold back soil or water while also providing lateral support for excavations.
Coastal protection:
Sheet piling can protect coastal areas from erosion, waves, and storm surges. They can also be used to construct breakwaters and jetties.
Cofferdams:
We use Sheet piles to build cofferdams, which are transient obstructions in water to facilitate the construction of piers, bridges, or other water-based constructions.
Underground structures
We use Sheet piles to construct underground constructions such as basements or underground parking garages. They support the lateral structure and restrict soil or water intrusion.
Sheet piles have various advantages, including their versatility, ease of installation, and durability. Moreover, they offer an affordable option for projects that need lateral earth support. However, adequate design and installation are essential for guaranteeing the sheet pile wall’s stability and safety.
Advantages of sheet pile
Sheet piles provide several advantages in construction projects that require lateral earth support. Following are some of the key benefits of sheet piles:
Versatility: Sheet piles find applications in a variety of construction projects, including retaining walls, shoreline protection, cofferdams, and underground structures.
Speed of installation: We can install Sheet piles quickly and efficiently using impact hammers or vibratory drivers, which can reduce project timelines and construction costs.
Durability: Since the material of construction Sheet piles is steel or other durable materials that can withstand harsh environmental conditions, including exposure to water, corrosion, and extreme temperatures, they are highly durable.
Cost-effectiveness: Sheet piles generally prove to be a more affordable alternative to other types of foundation systems for projects requiring lateral earth support since they need less excavation and backfilling.
Minimal disturbance: Sheet pile installation creates minimal disturbance to the surrounding soil and structures since we drive the piles into the ground without the need for excavation or other site preparation.
Reusability: Sheet piles offer easy removal and reuse in other projects, making them a sustainable and eco-friendly alternative.
We use Sheet piles for temporary and permanent structures and are available in a wide range of lengths, sizes and steel options.
We can install Sheet piles rapidly using silent and vibration-free methods. The installation is easier and faster than secant walls.
We can construct Cofferdams in almost any desired shape. Provide a close-fitting joint to form an effective water seal. Joints are designed to withstand the high pressure necessary for them to be placed in place. A little maintenance is needed above and underwater
Sheet piling types
Sheet piles are broadly classified as follows based on the material used for driving.
Steel sheet pile
Vinyl sheet pile
Wooden sheet pile
Concrete sheet pile
Composite sheet piles
Cellular sheet pile
Cellular sheet pile
Cold-formed sheet pile
Steel Sheet piles
Steel sheet piles are long, thin sections of steel that are driven into the ground to construct a retaining wall or a barrier. The most popular material for sheet piles is steel since we can lengthen it either by welding or bolting and has great water tightness as well as good resistance to severe driving stresses. They find extensive applications in civil engineering and construction projects to provide structural support for excavations, bridges, highways, and other structures.
Steel sheet piles are primarily made of hot-rolled steel and are available in a variety of shapes and sizes. We can link them together to form a continuous wall that acts as a strong barrier against the soil or water pressure. Steel sheet piles should endure heavy loads and give structural stability. Corrosion prevention techniques including coating and cathodic protection help increase the durability of steel sheet pile.
We frequently use Steel sheet piles in foundation work and deep excavations because they offer high resistance to lateral stresses and enable quick and simple installation. They are an eco-friendly option for temporary constructions because we can recycle them.
Overall, steel sheet piles are a versatile and cost-effective solution for a wide range of civil engineering and construction projects.
There are four basic forms of steel sheet piles, Normal sections, Straight web sections, Box sections and Composite sections.
Vinyl sheet pile
A vinyl sheet pile is a form of plastic sheet pile that finds applications in civil engineering and construction projects for a variety of purposes such as seawalls, bulkheads, flood walls, and retaining walls. Vinyl sheet pile primarily comprises polyvinyl chloride (PVC), a lightweight and long-lasting polymer that is resistant to corrosion, chemicals, and weathering. Because of its minimal maintenance requirements, simplicity of installation, and long-term durability, vinyl sheet pile is becoming more and more common in construction projects. Vinyl sheet pile, unlike traditional materials such as wood, steel, or concrete, does not require frequent maintenance or coating, making them a more cost-effective alternative in the long run.
Vinyl sheet pile is also environmentally friendly because it is reusable and does not leak dangerous chemicals into the soil or water. Because of its lightweight qualities, it is simple to transport and install, necessitating minimal use of heavy machinery and labour. Overall, vinyl sheet pile is a versatile and cost-effective solution for a variety of construction and civil engineering projects. Its durability, low maintenance requirements, and environmental benefits make it an appealing choice for contractors and engineers.
An effective alternative to steel sheet piling for bulkheads, seawalls and cutoff walls. They are also superior to alternative materials like concrete and wood. The main advantage of vinyl sheet piles is the superior corrosion resistance when exposed to seawater, where no oxidation occurs.
Vinyl sheet piles are lightweight and resistant to corrosion and chemical damage. They are often used in projects where environmental impact is a concern.
Wooden sheet pile
A wooden sheet pile is a type of retaining system comprising timber planks or boards. We commonly employ them in construction and civil engineering projects with a requirement for a retaining wall, either temporary or permanent. Hardwood sheet piles are a more environmentally friendly and long-lasting alternative to steel or concrete sheet piles. and they are widely utilised in places where environmental impact is a concern. In excavation work, we utilise them for braced sheeting and temporary structures. It must have some sort of preservative treatment for its utilisation in permanent structures above the water table. Even after treatment with a preservative, a timber sheet pile has limited life. Timber sheet piles are bonded using tongue and groove connections.
Features of wooden piles
Timber piles are not suitable in strata that contain gravel and boulders. Hardwood sheet piles are ideal for shallow excavations and we frequently utilise them in building projects where noise and vibration are a concern. They are lightweight and easy to handle, making them a popular choice for jobs requiring speedy installation. In comparison to other retaining wall materials, wooden sheet piles are also more affordable. Yet, there are significant drawbacks to using hardwood sheet piles. They are not as robust as steel or concrete sheet piles and require frequent maintenance to prevent rot and insect infestation. They may also be prone to warping and deformation if exposed to dampness for a lengthy period of time.
Hardwood sheet piles may not be suited for usage in places with high water tables or salinity in the soil, as these variables might accelerate the decomposition of the timber. Overall, hardwood sheet piles are an efficient and environmentally friendly option for small-scale building projects and temporary retaining walls. Yet, their durability and susceptibility to deterioration and warping make them unsuitable for long-term or large-scale applications.
Wooden sheet pile
Concrete sheet pile
Concrete sheet piles are retaining walls constructed from precast reinforced concrete sections. We frequently employ them in civil engineering and building projects with a requirement for long-term retaining structures.
We must handle and drive the piles carefully, and provide the necessary reinforcement. The most common application of Concrete sheet pile is in deep excavations where soil conditions are unfavourable and we require lateral support. They are impermeable and can withstand hydrostatic pressure, making them excellent for usage in places with high water tables. We provide a capping to the heads of the piles by casting a capping beam, while we cut the toes with an oblique face to make driving and interlocking easier. They are relatively heavy and thick, and while driving, they displace significant amounts of the earth.
The driving resistance rises as a result of the considerable volume displacement. Concrete sheet piles are also resistant to weathering, corrosion, and erosion, making them a durable solution under extreme conditions. Concrete sheet piles are available in a range of dimensions and we can interlock them to create a continuous wall. We can place them in a variety of ways, including driving, vibrating, and pushing. The method of installation depends on the accessibility to the site, the depth of the installation, the state of the soil etc.
Concrete sheet piles are a strong and long-lasting alternative, but their installation may be more costly and time-consuming than that of other retaining wall materials. However, installing them requires large machinery, which can be difficult in places with restricted access or space. Overall, concrete sheet piles are a viable option for permanent retaining walls in deep excavations and severe soil conditions. They are a preferred option for projects involving coastal protection and flood control due to their strength and resistance to water and erosion.
Aluminium sheet piles
Aluminium sheet piles are lightweight, strong, and corrosion-resistant, making them an ideal choice for projects that require a lightweight and durable material.
Composite sheet piles
We manufacture Composite sheet piles from a combination of materials, such as steel and concrete, to provide additional strength and durability. They often find applications in projects that require high load-bearing capacity.
Cellular sheet pile
We usually design Cellular sheet pile with hollow sections that allow for increased strength and load-bearing capacity. They find application in projects that requires a high degree of lateral support.
Cold-formed sheet piles
Cold-formed sheet piles are made by bending steel sheets into a desired shape. They find application in projects requiring lower strength and load-bearing capacity.
Conclusion
Each type of sheet pile has its own advantages and disadvantages, and the choice of material and design will depend on the specific requirements of the project. Proper design and installation are essential to ensure the stability and safety of the sheet pile wall, and consultation with an experienced engineer is recommended before selecting a specific type of sheet pile for a project.
Steam distillation is a separation process in which we separate a mixture of immiscible components by introducing steam and subsequently condensing the vapours. In this blog, I will walk you through steam distillation and its principles. First, let us understand the instances in which we opt for Steam distillation over other separation processes.
In the typical distillation process, we usually have a mixture of components that are miscible with one another. The vapour pressure that the combination exerts on heating depends on the components that make up the mixture.
To start boiling, the vapour pressure of the mixture should become equal to the atmospheric pressure or the pressure to which it is subjected to. Hence we must heat the system of the liquid mixture to a temperature where the system can create enough vapour to equalise the operating pressure or the atmospheric pressure.
The temperature that must be attained depends on the operating pressure; if it is less than one atmospheric pressure, the temperature that is to be attained is relatively lower; if it is greater than one atmospheric pressure, the temperature to be attained is relatively higher.
In some circumstances, it might not be possible to perform this. Some of those instances are as follows:
When separating materials with very high boiling points, we have to supply more heat to raise the temperature of the mixture. As a result, the procedure uses more energy and is more expensive.
If the mixture contains any thermally unstable components, raising the temperature too high could cause the components to decompose and have an impact on their qualities.
The process becomes energy-intensive if we have a binary combination in which one component boils at a high temperature while the other is non-volatile in nature.
We can easily handle these situations using the method of steam distillation.
Steam Distillation Principle
In the previous blog, we saw Raoult’s law which states that the partial pressure of each component in a miscible ideal mixture is equal to the product of its vapour pressure and mole fraction.
Pa = Xa * Pv
Hence it is clear that the liquid components can’t exert their actual vapour pressure but a corrected vapour pressure (or what we call the partial pressure) which is always less than its pure component vapour pressure ( since mole fraction is always less than 1 )
But, in the case of liquid mixtures in which the components are non-miscible, they can exert their entire vapour pressure as its partial pressure. That is, the total pressure becomes equal to the sum of the individual vapour pressures for immiscible liquid mixtures. Their combined vapour pressures can easily reach the external pressure before the vapour pressure of either of the individual components cross it. Hence the boiling point of the mixture would be lesser than the boiling point of either of the components.
Now, let us assume that water is one of the components in the immiscible mixture. Then we can bring that mixture to a boil at under 100 0C in one atmosphere ( Boiling Point of water at 1 ATM = 100 0C ) if we keep the pressure constant at 1 ATM. In other words, we can lower the operating pressure needed to boil the mixture by introducing steam.
The main concept behind steam distillation is that we use steam to help create the pressure needed to balance the operating pressure. We must be careful to only employ components that are immiscible with water while using steam.
Steam Distillation Process
Consider a binary mixture where component A is a high-boiling component and component B is a non-volatile component. Let’s say A is insoluble in water. We feed the mixture into the column. Using a steam coil, we raise the feed mixture’s temperature. A sparger forces the steam through another steam line. Steam enters the column through the feed mixture and adds to the vapour pressure. When it reaches the working pressure, it causes the creation of vapours of A at a significantly lower temperature. The non-volatile component is eliminated as residue but remains in the feed. Steam and Component A is routed via a condenser where they are easily separated after condensation.
Steam Distillation Advantages
We frequently use steam distillation since it has various advantages over other extraction methods. They are as follows:
the process produces organic compounds devoid of solvents;
Additional separation procedures are not necessary;
It has a huge processing capacity on an industrial scale;
Inexpensive equipment
Shall we wrap up?
Conclusion
In this blog, we saw the process of steam distillation, its advantages and its applications.
Calculating the unit weight of steel bars with various diameters is crucial when creating a schedule for bar bending. The total weight of steel bars/TMT bars weight required for the project’s construction can be calculated once we know the unit weight of steel.
Steel is the most commonly used structural material. Steel’s basic components include metallic iron, non-metallic carbon, and minor amounts of nickel, silicon, manganese, chromium, and copper, among others. High tensile strength makes it a popular construction material for civil engineering projects. Steel reinforcement bars, often known as rebar, are placed in concrete members to enhance their tensile strength. As we all know, steel is utilised to construct structural members such as columns, beams, footings, foundations, and building slabs. Steel bars of various sizes are supplied by the manufacturer, with lengths of 12 metres or 40 feet.
Why Unit Weight of steel bars Calculation is Important?
It is essential to comprehend the weight of steel bars since we estimate them as 100 metres 20 mm bar, 100 feet 16mm bar, and so on (is the sign for diameter). Steel bar manufacturers, on the other hand, will not interpret this notation and will measure the steel bars in weight. So we have to order them in kilogrammes, quintals, or tonnes. This article will go through how to use the steel weight formula to determine the steel bar’s weight.
You may run into terminology like “carpet area,” “built-up area,” and “super built-up area” if you’re considering purchasing a home. There are various types of areas in a building’s floor plan. Reading a floor plan is an important skill for a civil engineer to have. These are various methods of describing a property’s area. In this article, we will see about the different types of areas.
We should be informed with the following building construction practises before making home buying plans. Following are the terminologies usually followed in dealing with building construction.
Plot area
Built-up area or Plinth area
Carpet area
Setback area
Super built-up area
Before getting into these terms first we have to know what is RERA
Real Estate Regulation and Development Act, 2016, (RERA)
The Real Estate Regulation and Development Act, 2016, (RERA) is an act established by the Indian parliament. The main objective of RERA is to give prompt information between the buyers and sellers. This increases transparency and reduces the chance of cheating.
There are three different ways to calculate the area of the property.
In terms of the Carpet area
In terms of Built-up area
In terms of Super built-up area
While buying a property buyer should pay for the area which is usable. RERA provides safety of money, buyer protection and balanced agreement.
Areas of Building
Plot area (Areas of building)
The plot area includes the complete area which you own. This area comes under the fencing.
Plot area
Carpet area (Areas of building)
Carpet area is a term which the real estate agent uses the most. It is the area of the building which can be covered by using carpet. It is also called a net usable floor area.
Carpet Area = Total floor area – Area of internal/external walls
But as per RERA Carpet area = Total Floor area – Area of external walls
According to RERA flats should be sold on the basis of carpet area. The carpet area as per RERA is the area of usable spaces such as bedrooms, kitchen, bathroom, toilet etc. It also includes an area covered by internal partition walls. It excludes areas such as Balcony, utility areas, external walls area, open terrace area, lift, lobby, staircase etc. Mostly carpet area is 70% of its built-up area.
Carpet area
Plinth area
The plinth area is also known as the Built-up area. It is the total area of the building within the plot area. It is mostly 30% of the total plot area.
Built-up Area = carpet area + Area of walls
It includes living room, bedrooms, utility, bathroom, wall thickness, kitchen, balcony closed staircases etc. and excludes open terrace area, lift, open staircase, swimming pool etc. It is 10 to 15 % more than the carpet area.
Plinth area
Super built-up area
Super built-up area was used to measure the area of property before the RERA act came into existence. Because the super built-up area lowers the rate per square foot. Saleable area is another name of super built-up area.
Super Built-Up Area = Setback area+Built-up Area+20% of common area
Super built-up area includes common areas like swimming pool, clubhouses, lobby, staircase, Lift, etc. and the built-up area of the flat.
Set back area
Set back area is the space between the boundary and the building. It is the minimum open space necessary around the building. As per the municipal regulation a specific margin should be provided between building and road.
Setback area = Built-up Area – Plot area
Setback area
This provides sufficient ventilation, ease in vehicle movement and protection from other entities
Types of doors commonly used in residential, commercial, and industrial construction depend on the application area, durability required, the purpose of the door, etc.
What is a door?
A door is a movable barrier or mechanism for opening and closing an entranceway or a building/room. The purpose of the door in this urban environment is security and privacy. Apart from security, safety, and privacy, an aspect of art, beauty, and elegance is associated with it. The entrance door acts as a warm welcome to the areas inside.
This article is about the types of doors popularly used in civil construction.
Doors come in a number of types. The selection of a door type, on the other hand, is determined by the location, purpose, aesthetic needs, material availability, security, and privacy. Doors types are typically classified as follows.
Location based
Based on material
Based on operation mechanism
Types of doors in civil engineering– location based
The doors types are classified as follows
Exterior Doors
Interior Doors
Exterior door
An outside door is one that allows entry to a building/house. An outside door’s main function is to safeguard the building as well as the security and privacy of the occupants of the building. While selecting an exterior door, style, colours, finishes, and aesthetic looks to match the architectural theme must be considered.
Interior door
Interior doors provide access to interior spaces like bed, kitchen, special functional rooms, toilets, etc. However, choice of material and type depends on the nature of privacy, security, and purpose of the room. Interior doors used to be lighter than exterior doors.
Types of Doors – Based on Materials
The door choice is confirmed based on the material to be used. For that, we should have a better idea of the readily available, durable, and aesthetically matching materials. Following are the popular choices of doors based on materials used in construction nowadays.
Wooden doors types are the most common and premium choice for both external and internal doors. They are the preferred choice due to their classy and elegant looks, high durability, and ability to match any architecture theme. Moreover, they are aesthetically pleasing and are widely available on a reasonable budget. Wooden doors can be custom-made for any functional requirements and design. They are the oldest material used and never lose their sheen even after long years.
wooden door
Easily available
Easy working
Best material for front doors due to its high durability.
Used for any functional requirement.
Wooden doors are mostly polished rather than painted for exposing the natural grain looks.
Simple and easy installation.
Carving works are easily done on wooden doors.
Wooden doors are soundproof, got high thermal insulation capabilities and are strong.
Demerits of wooden doors
Even though wooden doors are superior materials they have their demerits also. However, needs periodic maintenance to retain the sheen and looks.
Needs periodic maintenance to retain the sheen and looks.
Wooden doors on long exposure to moisture may deteriorate.
Prone to termite attacks.
May sags
Glass Doors
Glass doors are for areas where the availability of natural light and open feeling is the main functional requirement. They are mainly used in areas where privacy is not a prime factor-like back yard, balcony doors, cabin doors, etc.
Glass doors are elegant and give an enhanced look to the house. However, the main problem with glass doors is the safety and privacy factor and the possibility of glass breaking. The glass breaking problem is managed by using small glass pieces for front doors. The glass should be safety glass or toughened glass.
Metal Doors
Steel is one of the preferred and favorite alternatives to wood for both external and internal doors. Mild steel or Galvanized steel is used for the manufacturing of doors. These doors are manufactured in solid and hollow types and are a safer, durable, and stronger option when compared to wooden doors.
metal door
Steel door frames are usually combined with wooden, PVC, steel, and flush door shutters. Steel door frames are manufactured by pressing steel sheets, angles, channels, etc. Holdfasts and hinges are welded to the steel frames. Steel frames are popular and are used for residences, factories, industrial buildings, etc. They are economical than conventional wooden frames.
Metal door shutters are manufactured from high-quality cold-rolled Mild Steel (MS) sheets, with a steel face and rock wool or foam insulation. Steel is a more economical and stronger option compared to other materials even though steel may not look as attractive as wooden or glass doors. Metal doors are available in different tones and shades. They are durable, have minimal maintenance, and provide excellent security.
Types of Doors – Flush Doors
The flush door is made of a timber frame covered with plywood from both sides. However, the hollow core is filled with rectangular blocks of softwood just like block boards. Flush door surface finished with decorative finish by fixing veneers. The flush door is usually laminated or veneered to match the architectural themes. These doors are usually hinged type and have one side opening only. The frame can be of wooden, PVC, or steel. Flush doors got a seamless look and are economical, look elegant, and are easily available in the market.
flush door
While providing these doors for toilets, baths; the inner face of the door should be covered with aluminum sheets to protect against water.
PVC Doors
PVC or polyvinyl chloride doors are a very popular choice for doors. They are available in a range of colors and styles. Furthermore these doors have high resilience, are anti-destructive, termite-proof, moisture-resistant, lightweight, etc. As a result they are best suited for areas with moisture chances like bathroom areas. Polyvinyl doors come in a variety of designs types. colors, style and looks beautiful. Similarly these doors do not corrode like steel or disintegrate like wood and do not need much maintenance. They are very simple and easy to install and are scratch-proof. These doors are not preferred for front doors due to their lightweight characters and inability to resist environmental conditions. These doors are cost-effective when compared to wooden and metal doors.
Types of Doors – UPVC Doors
uPVC stands for Unplasticised Polyvinyl Chloride. It is a form of plastic that is hard and inflexible, also known as rigid PVC. UPVC doors are a preferred choice of architects and home owners due to the superior qualities they offer when compared to other door materials like wood, metal , PVC etc
Easy to clean and maintain – UPVC doors can be cleaned by simply wiping with a soft cloth soaked with mild detergents even though they may not peel or cracks after years of usage.
UPVC Profiles are manufactured to accommodate double glass units (DGU) in fact provides excellent thermal and acoustic insulations. Furthermore glass panes can be substituted with reflective glass to reflect sunlight and keep the rooms cooler in summers.
Durability – UPVC is a highly durable material, in addition to that allows for the construction of doors and windows that are long-lasting. In addition to all above they are dust-proof, termite-proof, moisture, and weather-resistant.
Ease of installation – Similarly UPVC doors are very fast and easy to install.
UPVC doors
Types of Door – Aluminium doors
Aluminium doors due to their excellent and durable qualities are the most preferred option for designers and architects. They are durable, strong and maintenance free material. The fabrication and installation is very easy and got the choice of using as member for DGU units for thermal insulation applications. Aluminium is expensive, however considering the superior qualities aluminium is preferred in most of the areas.
Conclusion
Apart from the types described above there are a lot of doors varieties available in the market to cater each and every situation and applications. However, these door type selection has to be in line with the requirements.
The ultrasonic pulse velocity test, or UPV test, is an example of a non-destructive concrete test. Generally, hardened concrete is subjected to non-destructive testing (NDT) and destructive tests (DT). Concrete is the world’s oldest and most significant construction material. Therefore, concrete testing is crucial for assessing the stability, strength, durability, and condition of structures.
Non-destructive testing of concrete is a way of analysing concrete structures without causing damage. This aids in ensuring the structural quality and condition. The strength of the concrete is also influenced by various characteristics, including hardness, density, curing circumstances, ingredient quality, workability and water-to-cement ratio, etc.
This article discusses the UPV test, which is one of the most well-liked and reliable non-destructive tests carried out on concrete structures.
The most efficient and fast method of testing concrete is through ultrasonic pulse velocity tests, or UPV tests. The quality of concrete is assessed using the results of UPV tests, which evaluate the period of travel of ultrasonic pulse waves. A 50–55 kHz range must be maintained for the ultrasonic pulse wave’s frequency. The pulses are generated by the UPV tester’s pulse generator and are allowed to travel through the concrete. By monitoring the traversing distance and the duration, the pulse velocity can be determined. Higher velocity indicates that the density and elastic modulus of the concrete are higher.
Cracks and defects in the structure are detected using UPV tests. Significant variations in pulse velocity values are indicative of broken and degraded concrete. The concrete’s density and wave velocity are related. Therefore, this test has a tremendous potential for evaluating the quality of concrete.
Relevant IS code for Ultrasonic Pulse Velocity Test (UPV Test)
IS-13311 (Part 1):1992 (Reaffirmed- May 2013) “Non-Destructive Testing of Concrete- Methods of Test (Ultrasonic Pulse Velocity)”
The UPV tester is the name of the type of equipment used to measure ultrasonic pulse velocity. The following accessories are included in ultrasonic pulse velocity tester.
Electrical Pulse generator
Pair of Transducers (probes)
Amplifier
Electronic timing device
Ultrasonic Pulse Velocity Tester
Principles of Ultrasonic Pulse Velocity test
The electrical pulse generator generates pulses that are sent through the UPV tester’s transducer. Through the concrete surfaces, the pulse generates many reflections. Using the formula shown below, the pulse velocity is calculated.
Pulse velocity, V = L/T
where L is the traverse distance, T is the time for the receiver to receive the pulse
The geometry of the material is unrelated to the UPV test. Better concrete strength is associated with higher velocity and vice versa. One of the dynamic tests for concrete is the ultrasonic pulse velocity test.
Objective of UPV tests
The main objectives of the ultrasonic pulse velocity test or UPV tests are
To learn the homogeneity of the concrete.
Determines the presence of cracks, voids and imperfections.
To calculate the elastic modulus of concrete.
Finds the quality of concrete relative to the standard requirements.
To determine the age of concrete.
Factors affecting Ultrasonic pulse velocity test
The UPV test detects cracks and assists in structure development. However, a number of factors influence how pulse velocity is measured. As a result, compressive strength cannot generally be approximated from the pulse velocity. The following are the elements that impact the UPV test.
Presence of reinforcement
Water content
Mix proportion
Temperature of concrete
Concrete age
Stress level of concrete
Methodology of Ultrasonic Pulse velocity tests
Piezoelectric and magneto strictive types of transducers are suitable for use with the UPV test. Additionally, its frequency range should be between 20 and 150 kHz. The electronic timing device monitors time with an accuracy of 0.1 microseconds.
The transducer transmits the waves that travel through the concrete surface. The receiver transducer detects the electric signals that are generated once the pulse waves are transformed to them. The traversal length will be displayed as ( L). The electronic timing device calculates how long it takes for signals to arrive. Time is shown as (T).
The Electronic timing device measures the receiving time of the signals. The time is denoted as (T).
Pulse velocity (v) = L/T
There are three common methods for doing UPV tests. They are direct method and indirect method.
Direct Method of UPV Testing
Indirect Method of UPV Testing
Methodology of UPV test
Direct method
The maximum energy is transmitted at right angles to the face of the transmitter. As a result, to achieve the greatest results, the receiving transducer must be placed on the side of the transmitting transducer. This is referred to as the direct approach or cross probing.
Ultrasonic Pulse velocity test -Types
Indirect method
In some circumstances, the opposite side of the structure may be inaccessible. The receiving and transmitting transducers are installed on the same face of the concrete members in this scenario. This is known as the indirect method or surface probing. This approach is less effective than the direct approach. The test findings are mostly influenced by the surface concrete, which has different properties from the structural components’ core concrete.
Result interpretation of UPV testing
The density and elastic modulus of concrete are correlated with the ultrasonic pulse velocity. This in turn depends on the components, mixing processes, placement techniques, concrete compaction and curing, casting temperature, etc.
The main causes of internal cracks and pockets in concrete are lack of compaction and concrete segregation. Lower pulse velocity values are a result of these concrete defects. However, the laboratory tests might have confirmed a well-designed concrete.
The range of pulse velocity in the direct method is as shown below.
Above 4.5 Excellent
3.5 to 4.5 Good
3.0 to 3.5 Medium
Below 3.0 Doubtful
Conclusion
The final assessment of compressive strength from UPV is not the sole criterion used to determine concrete strength. The strength is confirmed by comparing it to a compressive strength estimate derived from the same ingredient mix and conditions. The results of the UPV test and site tests conducted using similar ingredients may be correlated. When compared to actual UPV intensities, the numbers may change by about 20%.
Bitumen types for road layers are a vital topic to comprehend when it comes to road construction. Bitumen is preferred for flexible pavements in road construction because it has many advantages over other pavement construction materials. This article will demonstrate the importance of bitumen in road construction and the types of bitumen for road construction. Furthermore, bitumen emulsion types for road layers, different bituminous materials, cutback bitumen, bitumen grade, and bitumen attributes will be highlighted in this article.
The flexible pavement structure consists of the following layers:
Tack Coat
Binder Course
Prime Coat
Base Course
Subbase Course
Subgrade Course
Keep in mind that the primary component of the road is not protective asphalt. Protective asphalt is deployed to safeguard the road’s surface. Every layer mentioned above uses a different type of bitumen. We will illustrate what types of bitumen are used in each of these layers.
Tack Coat – Bitumen types for road layers
The application of coatings is a critical phase in the construction of asphalt roadways. Generally, a tack coat is a thin layer of asphalt emulsion or liquid bitumen used in between layers of hot mix asphalt to prevent slippage. Mostly, MC30 cutback bitumen, CRS-1, and CRS-2 emulsion bitumen are utilised in a tack coat layer of bitumen. The lower layer is sealed by the presence of a tack coat, which also increases the strength of both asphalt layers.
MC-30 is a medium-curing cutback bitumen that is ideal for cold climates. Basically, asphalt emulsions are the most often used tack coat materials. However, the most widely used slow-setting emulsions are SS-1, SS-1h, CSS-1, and CSS-1h (1). The usage of rapid-setting asphalt emulsions like RS-1, RS-2, CRS-1, and CRS-2 for tack coats is also on the rise.
The base course and the surface course are separated by the binder course. Generally, a binder course is used to keep the road surface from moving. Because the binder course is made out of coarse aggregates, less bitumen is utilised in the manufacture of this asphalt. In the hot asphalt of the binder course, various grades of pure bitumen can be utilised. The various grades of pure bitumen used in binder courses are listed in the table below.
Penetration Grade
Viscosity Grade
30/40
VG 10
40/50
VG 20
60/70
VG 30
80/100
VG 40
120/150
Bitumen types for road layers
Prime Coat – Bitumen types for road layers
A prime coat is a coating that is applied directly to the base layer. The primary objective of utilising the prime coat is to improve the bond between the base layer and the asphalt mix layer. It also fills in the voids. A priming coat might aid in sealing the base layer. The bitumen in prime coatings is either CSS or CMS.
Prime coats aid in reducing dust while protecting the granular base’s integrity throughout construction. In the event of a foundation that will be covered with a thin hot mix layer or a chip seal for a low-volume roadway, priming enables a good bond between the seal and the underlying surface, which might otherwise delaminate.
A primary coat is primarily responsible for safeguarding the substrate of a construction project before applying additional layers. They can also function as a binder with secondary and tertiary compounds in the preparation of asphalt, improving the adherence of the layers. Following the prime coat, a tack coat is applied to provide an adhesive bond between the tack coat and the subsequent layer of coating. For asphalt prime coat systems, the tack coat is one of the most vital parts of the process, as it connects the subsequent layers and forms the base of those layers’ strength.
Base Course
The base course is placed directly on top of the subbase course. This layer has a higher permeability than the sub-base layer because it is composed primarily of coarse aggregates. Basically, the base course, which is the first layer in direct contact with traffic, moves the weights from the upper layers to the sub-base course. Different base courses used in pavement include sand or stone base, macadam base, and bitumen base.
road-layers-of-flexible-pavement
Sub Base Course
The first layer of flexible pavement constructed on the ground is the sub-base course. This layer is typically composed of river sand, an alluvial cone, and broken rock. Bitumen and cement can be used to stabilise the sub-base soil.
Sub Grade
It is the surface upon which further pavement layers such as the sub-base course, base course, and asphalt layers are placed. The subgrade absorbs any load tension or weight that is transferred from the top levels. A good subgrade should be able to support weights for a considerable amount of time without deforming.
Protective Asphalt
Generally, Protective asphalts are used to seal the road surface and improve the asphalt temporarily. However, It should be noted that asphalt sealing can cause the asphalt to become more slippery. Pure bitumen with low humidity and soluble bitumen are both utilised in protective asphalt. Because of its quickness and ease of installation, protective asphalt is more cost-effective than hot asphalt. There are various varieties of protective asphalts, some of which are listed below:
Seal coat
Slurry seal
Chip seal
Micro-surfacing
Fog seal
Seal coat
A seal coat is used to provide a long-lasting surface texture and to keep the surface waterproof. However, this kind of protective asphalt can be made using a variety of emulsion bitumen types, including CSS-1, SS-1h, SS-l, and CSS-1h.
Slurry Seal
Generally, a slurry seal is used to lessen the harm done by bitumen oxidation. In the slurry seal, emulsion bitumens SS-1, SS-h1, CSS-1h, and CQS-1h are used. A slurry seal is appropriate for pavements with little to moderate damage, such as narrow cracks. However, it is not appropriate for severe damage such as holes.
Chip Seal
A chip seal is a thin protective surface that is applied to a pavement or subgrade. Water cannot easily seep through the base layer due to the chip seal. This layer also prevents freezing in areas where the temperature is below zero. Adding this layer improves the road’s reflectiveness for nighttime driving. A rapid-setting emulsion containing a CRS-2, RS-2, HFRS-2, and PMB is the best type of bitumen for chip sealing.
Micro Surfacing
Micro-surfacing aids in the sealing of cracks and the protection of existing bituminous layers against surface voids and minor ruts. Among the benefits of adopting this layer are environmental compatibility, cost-effectiveness, and fast construction time. PMB bitumens such as PMCQS-1h, PMQS-1h, and CQS-1P are suited for it.
Fog Seal
A fog seal is intended to neutralise the oxidation process that occurs over time. This layer protects the pavement surface by leaving a hard layer. This layer employs emulsion bitumen such as SS-1, SS-1h, CSS-1, or CSS-1h.
Bitumen for roads is an important topic to understand when it comes to road construction. Bitumen is used in road construction because of the wide range of features and advantages it possesses over other pavement construction materials. The significance of bitumen in the construction of roads will be demonstrated in this article. In addition, we shall see bitumen road layers, various bituminous materials, cutback bitumen, bitumen grade, and bitumen properties.
Generally, tar is made by heating coal inside a chemical apparatus. Most tar is produced from coal as a byproduct of coke production, but it can also be produced from petroleum, peat or wood.
The major steps in tar manufacturing are,
Coal undergoes carbonation and produces crude tar
Crude tar undergoes distillation/ refining and produces a residue
The residue blends with distilled oil fraction and produces tar
Desirable properties of bitumen- an important topic in bitumen for roads
Bitumen for roads – Properties
The desirable properties of bitumen are,
Viscosity of bitumen during mixing and compaction is adequate
Bituminous material should not highly temperature and susceptible
In presence of water the bitumen should not strip off from aggregate
The adhesive property of bitumen binds together all the components without bringing about any positive or negative changes in their properties
Bitumen is insoluble in water and can serve as an effective sealant
Due to versatility property of Bitumen it is relatively easy to use it in many applications because of its thermoplastic property
Bitumen play a vital role in distributing the traffic loads on the pavement to the layers beneath
Bitumen for roads – Types of Bituminous materials
Okay. So, what are the types of bituminous materials that are used in flexible pavement construction? Below is the list for you.
Paving grade material
Modified bituminous binder
Cutback bitumen
Bitumen emulsion
Among the list, cutback bitumen is the major. Let me tell you more details about cutback bitumen.
Cutback bitumen
Cutback bitumen is the bitumen the viscosity of which is reduced by a volatile diluent. It is used in low-temperature mixing.
Three types of cutback bitumen are available
Rapid curing
Medium curing
Slow curing
The diluent while mixing varies with the type of cutback bitumen.
Type of cutback bitumen
Diluent
Rapid curing
Nafthal, gasoline
Medium curing
Carosine or diesel oil
Slow curing
High boiling point gas oil
Type of cutback bitumen and suitable diluent
Bituminous emulsion
Bitumen emulsion
A bitumen emulsion is a liquid product in which a substantial amount of bitumen suspended in a finely divided condition in an aqueous medium and stabilized by means of one or more suitable material
To determine the grade of bitumen, penetration test is conducted. The results are expressed in 1/10 mm. When penetration value is represented as 80/1000, it is called grading of bitumen.
The old method of grading is viscosity test. Two viscosities kinematic and absolute and penetration value by penetration test results are collected. Based on this, bitumen is graded. The tables shows the grade of bitumen and values of viscosity in accordance with penetration.
Grade of bitumen
Absolute viscosity
Kinematic viscosity
Penetration
VG 10
800
250
80- 100
VG 20
1000
300
60- 80
VG 30
2400
350
50- 70
VG 40
3200
400
40- 60
Grade of bitumen and viscosity
Let me tell you the application of each of the grade of bitumen now.
VG- 10- Used in spray application since viscosity is very less
VG- 20- Used in cold area
VG- 30- Commonly used in India
VG- 40- High grade bitumen used in high traffic areas
Okay. So, lets’ learn about the bituminous layers.
The bitumen road layers come in the surface layer shown in the figure above. The figure below shows that. Bituminous mix consists of aggregate and binder. Aggregate consists of coarse aggregate, fine aggregate and filler less than 0.075mm.
Bitumen road layers
Bituminous concrete consists of aggregate and bitumen.
Thickness of base course depends on grading of aggregate
Dense graded aggregates are provided in base course. That is the permeability will be very less
Number of voids should be very less
Dense bituminous macadam should be given as a binder course
So, the trip is over. Hope the time you spend for reading about the bitumen for road was worth it.
Aluminium composite panel, also known as an ACP sheet, is a modern panelling material used for building exteriors (facades), interiors, kitchen cabinets, and signage applications.
Aluminium composite panels are flat panels having a non-aluminium core sandwiched between two thin coil-coated aluminium sheets. Aluminium Composite Panel is the most durable and flexible decorative surface material available, with enhanced performance attributes. This article discusses the production process, ACP sheet types, advantages, and applications.
What is an Aluminium Composite panel or ACP sheets ?
Aluminum composite panels are made up of two thin layers of aluminium sheets sandwiched by a polymer core. ACP sheet’s polymer core is made of Low-Density Polyethylene (LDPE) or Polyurethane. These polymer cores are made of components that are flammable and not fire-resistant. Because aluminium has a low melting point, the Aluminium composite panel is more flammable when the combustible polymer core is present. The presence of a combustible polymer core limits the use of Aluminium composite panel in fire-prone areas.
To improve fire resistance, polymer cores should be specially treated or over 90% (Non-Combustible Mineral Fiber FR core) sandwiched between two layers of aluminium skins should be used. To preserve the ACP sheets, polyvinylidene fluoride (PVDF), fluoropolymer resin (FEVE), polyester coating, and other materials are applied. The typical thicknesses of aluminium composite panel are 2 mm, 3 mm, 4 mm, and 6 mm.
Aluminium Composite Panels – Façade
Types of Aluminium Composite Panels (ACP)
Depending on the usage and fire rating standards ACP sheets are classified into two categories
Non fire rated grade
Fire rated grade
Non fire rated Aluminium Composite Panel (ACP)
Two thin layers of aluminium sheets plus a sandwiched polymer core make up aluminium composite panels. Aluminium Composite Panel’s polymer core is made of polyurethane or low-density polyethylene (LDPE). These Aluminium Composite Panels are not fire-rated since they are flammable and could catch fire. The use of these sheets is restricted based on the fire rating. The image below depicts a typical cross-section of an ACP sheet that is not fire-rated.
Non Fire rated or Standard Aluminium Composite Panel – Typical section
Fire rated Aluminium Composite Panels
Depending on the core composition, fire-rated Aluminium Composite panel can withstand fire for up to 2 hours. The core materials are the fundamental distinction between ACP sheets that are fire-rated and those that are standard. While the fire-rated ACP has a specially formulated fire-resistant mineral core, the standard ACP uses LDPE/HDPE as its core material. Fire resistant mineral core uses Magnesium hydroxide as core for enhanced fire retardant qualities. As the name suggests, Fire Grade Aluminium Composite Panels have the unique capability to withstand extreme temperatures. The highest grade ACP is fire retardant ACP (A2 GRADE), which contains over 90% inorganic material content.
Aluminium Composite Panels are widely used nowadays because of their countless unique properties. Let’s highlight a few of its unique features that set it apart from other panelling materials.
Light weight
When compared to other building materials like steel, Aluminium Composite Panel is lightweight. This significantly reduces the design loads on the structure with big spans and vast areas involved. Lifting and erecting ACP sheets is simple. This, in turn, minimises labour and construction costs while maintaining the schedule.
Flexible
The ACP sheet is flexible and very simple to use. The installation process is quick and simple, and the fixing framework construction is uncomplicated.
Availability and colour choices
This composite panel has exceptional flexibility because to the vast range of finishes it supports. Aluminium composite board can be textured, solid, mirror, or wood type to meet any architectural concept. The colour and feel of real stone and wood are effectively replicated on aluminium.
Environmental friendly
ACP is an environmentally friendly material that is composed of 85% recycled aluminium. ACP’s cover sheets and core material are both recyclable.
Dimensional stability
Aluminium composite panels got high dimensional stability and the material can remain stable for a long period without changing the dimensions.
Smooth and elegant
The exteriors of buildings can have a pleasant and attractive appearance because to the smooth, elegant ACP surface.
Cost
ACP sheet is the most economical panelling option when compared with other panelling materials. The cost depends on the core materials. The fire grade materials are costlier than standard non fire rated ACP.
Weather resistant and Durable
ACP panels are UV resistant and chemical resistant. They are unbreakable stain-resistant, weather-resistant, termite resistant, moisture resistant, and anti-fungal.
Applications of Aluminium Composite Panels
ACP sheet is mainly used for a wide range of applications due to its extraordinary qualities. Major uses of the ACP sheet are as follows.
External and internal architectural cladding
Internal partition
False ceilings
Signage
Machine coverings
Container construction
External and internal architectural cladding/partitions
For exterior cladding/façade applications, ACP sheets are used, thanks to their versatile qualities like UV resistance, fire resistance, and durability. ACP sheets come in a wide range of colours to match any architectural style. ACP sheet is the material of choice for facades and partitions because of its lightweight characteristics, simple fixing procedures, and quick construction.
Internal partitions
Aluminium Composite Panels in combination with aluminium, UPVC etc are used for office cabins and internal partitions. Partitions can be done with minimal space wastage.
Signage
ACP is used to render a wide variety of flexible exterior signs, as signage and hoardings are being used for exterior applications and must survive changes in temperature or weather
Interior work
ACP sheets are used for interior applications such as wall coverings, false ceilings, cupboards, portable kitchen cabinets, tabletops, column covers, and more.
Conclusion
ACP sheets are Green and environmentally friendly, easy to clean, and can shorten the construction period. ACP panels are resistant to corrosion, prevents acid and alkali, and other types of corrosion. Due to these versatile properties, ACP sheets are one of the popular choices in the construction sector.
Formwork in construction refers to a mould used to shape concrete into structural shapes (beams, columns, slabs, shells) for buildings and other structures. Concrete is one of the most popular building materials due to its exceptional properties and advantages. However, in order to create construction components, concrete must be poured into a specific mould. In order to achieve the desired shape precisely, concrete is occasionally poured into formwork, a type of temporary mould. Formwork types in construction can also be categorised based on the type of structural member they are used in, such as slab formwork for use in slabs, beam formwork for use in beams and columns, and so forth. The formwork and any accompanying falsework must be sturdy enough to support the weight of the wet concrete without experiencing significant distortion.
Timber formwork is the most prevalent type of formwork used for minor buildings. This article explores the various forms of formwork used in construction as well as their characteristics.
Formwork is frequently used in a range of shapes and sizes in building, roads, bridges, tunnels, corridor linings, hydroelectric power dams, agriculture headwork, sewage pipeline works, and other applications based on our design materials in the form of PCC and RCC. Falsework is the term for the structures that are needed for formwork in order to prevent movement during construction procedures. Formwork in construction requires a qualified crew and appropriate supervision to ensure high quality. Poor accuracy and expertise during the creation of the formwork lead to subpar work, which wastes time and money.
Formwork
25 to 30 per cent of the total price of concrete construction is made up of the cost of the formwork. For bridges, this cost proportion could be higher. However, depending on the complexity of the structure, this may exceed 60%.
Although there are numerous formwork materials, the following are general performance characteristics to satisfy the objectives of concrete construction is as follows.
Easy removal
Economy
Rigidity and strength
Less leakage
Supports
Easy removal
The design of the formwork should be such that it may be quickly removed with minimal pounding, resulting in less damage to the concrete.
Economy
Formwork serves no purpose in ensuring the stability of completed concrete. So, keeping safety in mind, its cost might be reduced. The formwork should be constructed with reasonably priced, lightweight, readily available materials that are both recyclable and reusable.
Rigidity and strength
Good formwork should be capable to withstand any form of live or dead load. Formwork must be properly aligned to the target line, and levels must have a plane and solid surface. When exposed to weather, the formwork’s material shouldn’t swell or warp. When choosing the formwork, take into account the temperature of the pour as well as the type of concrete being used because both affect the pressure that is applied. Furthermore, the formwork must be sturdy enough to bear the weight of both wet and dry concrete.
Less Leakage
Joints must not leak at any point.
Supports
Formwork needs falsework, which consists of stabilisers and poles, in order to stop moving while construction is being done. Formwork needs to be supported by sturdy, rigid, and rigid supports.
De-shuttering Period as per IS 456 – 2000 for formwork in construction
Let us have a look into the de-shuttering period of various structural components as per IS 456-2000
Sr. No.
Type of Formwork
Minimum Period Before Striking Formwork
1.
Vertical formwork to columns, walls, beams
16-24 hours
2.
Slab ( props left under )
3 days
3.
Beam soffits ( props left under )
7 days
4.
Props for Slab
(a).
Spanning up to 4.5m
7days
(b).
Spanning over 4.5m
14days
5.
Props to Beam and Arches
(a).
Spanning up to 6m
14days
(b).
Spanning over 6m
21days
De-shuttering period as per IS 456
Advantages of formwork in construction
Formwork is unquestionably necessary for all construction projects; its fundamental benefit is that no other technique can take its place.
Concrete structures can be swiftly and affordably built by using formwork.
A formwork provides suitable access and working platforms throughout the whole construction process, thereby, enhancing worker scaffold safety.
Formwork helps to reduce project timelines and costs by shortening the floor-to-floor building cycle time, which implies that more projects can meet their budgetary requirements. This, in turn, enables construction managers to provide precise on-time shuttering and de-shuttering of formwork resources, which improves project effectiveness and resource utilisation.
Formwork assists in creating a smooth concrete finish surface.
Types of formwork in construction
The following are the major types of formworks commonly used in construction.
One of the first types of formwork utilised in the construction industry was timber formwork. Basically, timber formwork is the most versatile form, is built on-site, and has numerous advantages. In comparison to metallic formwork, they are incredibly lightweight and easy to install and remove. Timber formwork is versatile and can be built to any shape, size, or height. However, for minor projects where the use of local wood is permitted, these kinds of formworks are cost-effective. Prior to usage, the lumber must, however, undergo a thorough inspection to make sure it is termite-free. Timber formwork also has two disadvantages that should be considered: it has a short lifespan and takes a long time on large projects. Timber formwork is frequently recommended when labour costs are low or when flexible formwork is required for complex concrete components.
Timber formwork in construction
The timber formwork should be well-seasoned, small in size, easy to nail without breaking, and free of slack knots. During shuttering, every face of timber that will make contact with the exposed concrete work must be even and smooth.
Plywood formwork
Generally, for plywood shuttering, sheets of waterproof, boiling-level plywood that are suited for shuttering are commonly used. These plywood sheets are attached to wooden frames to form the desired-size panels. Typically, plywood formwork is used in the sheathing, decking, and form-lining applications. Hence, Plywood formwork is the modern-day alternative to wooden formwork in construction. To support the concrete work, this formwork incorporates plywood. Plywood formwork results in a smooth concrete surface, which eliminates the need for concrete refinishing. Accordingly, with the use of large-size panels, a wider area can be covered. Basically, for jobs like fixing and disassembling, this might result in labour savings. The number of reuses is higher as compared to wooden shuttering. The number of reuses might be approximated to be between 10 and 15 times.
Plywood formwork in construction
Many of the same characteristics of timber formwork, such as strength, durability, and lightweight, also apply to plywood formwork. The ability of plywood shuttering to withstand moderate weather conditions is one of its key benefits. The surface of plywood seems to be sturdy, and it is robust enough to support the weight of concrete.
Metal formwork
Steel shuttering is composed of panels with thin steel plates that are connected at the edges by small steel angles. Suitable clamps or bolts and nuts can be used to secure the panel units together, Likewise, this type of formwork is used in the majority of bridge construction projects. Because of their long lifespan and adaptability, steel hardware and formwork are becoming more popular. Despite its potential cost, steel shuttering is beneficial for a wide range of applications and constructions. Basically, steel shuttering gives the concrete surface an extremely flat and smooth finish. It is ideally suited for circular or curved structures such as tanks, columns, chimneys, sewers, tunnels, and retaining walls.
metal formwork
Advantages of metal/steel formwork
It gives the surface of the member a highly smooth and levelled finish.
Steel shuttering has a long lifespan and is effective and strong.
The honeycombing effect is reduced and it is waterproof.
It can be used more than 100 times.
The concrete surface does not collect moisture through the steel shuttering. Likewise, it is simple to assemble and de-shuttering.
Aluminium formwork
Aluminium shuttering resembles steel shuttering. The main difference is that aluminium has a lower density than steel, which makes formwork lighter. There are a few things to consider before using aluminium in a construction project. Compared to steel, aluminium is less strong. Aluminium shuttering is cost-efficient when deployed in several construction projects engineered for repeated use. The major disadvantage is that once the shuttering is constructed, it cannot be changed.
Advantages of Aluminium Formwork:
A smoother, cleaner surface finish is produced.
Generally, Up to 250 re-uses were intended for aluminium formwork.
It’s also cost-effective if numerous symmetrical structures need to be constructed.
Disadvantages of Aluminium Formwork
The initial cost is higher since aluminium formwork is now more expensive. Such formwork is cost-effective when used in symmetrical building designs.
Setting up initially takes some time.
Professional services are necessary in order to align and maintain this kind of formwork.
In order to prevent future leaks, the formwork holes made by wall ties should be correctly blocked.
Plastic formwork
Interlocking panels or modular systems, which are both light and strong, are used to construct plastic shutters. Generally, small, repeatable initiatives like low-cost housing complexes are where it works best.
Basically, plastic formwork is appropriate for plain concrete structures. Due to its lightweight and water-cleanability, plastic shuttering is ideal for large segments and multiple reuses. Its primary drawback is that it is less flexible than timber because many of its components are prefabricated. However, large housing projects and structures with similar shapes are increasingly using these shuttering techniques.
On Tuesday, the Aditya Birla Group company announced that the 1.9 mtpa greenfield clinker-backed grinding capacity at Pali Cement Works in Rajasthan had been put into operation.
According to the corporation, this is a part of the first phase of capacity increase that was announced in December 2020.
With 5 different plant locations, the firm and its subsidiary can now produce 16.25 mtpa of cement in Rajasthan.
The total capacity of UltraTech Cement for the production of cement in India is currently 121.35 mtpa. Outside of China, UltraTech Cement is the third-largest cement manufacturer in the world, with a combined Grey Cement capacity of 121.25 MTPA.
Despite a rise in net sales of 15.78% to Rs 13,596, the cement manufacturer’s consolidated net profit fell 42.47% to Rs 756 crore.
Segregation is the separation of concrete ingredients from one another. Concrete is one of the most used construction materials. It consists of coarse aggregate, fine aggregate, cement and water. There are many reasons for the cause of segregation. This article is about segregation and bleeding and their types, causes and remedies.
Workability is an important property of concrete that reflects how easily we can place a particular concrete mix . Good concrete should be uniformly mixed and easily placeable without segregation or bleeding.
What is segregation in concrete ?
Segregation of concrete is the separation of ingredients in concrete. Since concrete is a non-homogeneous material, improper mixing is the main reason for the segregation. It occurs during transporting, handling and placing of concrete. Also, it affects the concrete properties. The strength of concrete decreases and leads to cracking. Therefore it should be properly mixed before use in construction.
segregation
Causes of Segregation in Concrete
A good quality concrete mix is prepared by considering factors like the size of aggregate, water-cement ratio, compaction, etc. They are many reasons for the causes of segregation. They are
Segregation is hard to measure since there is no particular test for determining it. However, the Flow table test measures the segregation. Also, the slump test of concrete can give an idea about segregation. Coarse aggregate in concrete tends to settle down from other ingredients. Usually, It occurs when the concrete mix is dry. While segregation by separation of water content occurs due to an insufficient amount of fine aggregates or due to the use of an excess amount of water content.
Segregation occurs when the principal ingredients in a concrete mix – in other words, gravel aggregate, cement, and water – separate prior to and during the curing process. Moreover, Segregation causes excessive amounts of water to rise to the surface. This process is know as bleeding. Bleeding is also similar to segregation in which the water in the concrete rises to the surface of the concrete. As a result, the concrete becomes porous and weak.
Bleeding affects its strength and its durability of concrete . Likewise, It breaks the bond between the concrete and steel reinforcement. However, a proper proportion of concrete ingredients and controlled vibration can reduce bleeding. Moreover, air entraining admixtures can also be used for reduce bleeding.
Bleeding of concrete
Causes of bleeding in concrete
The main causes of bleeding in concrete mix is as follows
Segregation is the main cause of bleeding in concrete
Types of Bridges in civil engineering can range from modest constructions to massive, eye-catching pieces of art – and everything in between. A bridge serves its sole purpose as long as it transports us across a gap. The required passage may be for a road, train, pedestrians, canal, or pipeline. A river, a road, a railway, or a valley may be crossed. Types of bridges are an important classification in civil engineering. In today’s blog, we are going to learn about different types of bridges in detail.
Types of bridges and Bridges design types in civil Engineering
The types of bridges are broadly classified as follows on the basis of form and type of superstructure
A dead load of a bridge is the weight of the bridge itself, plus the weight of whatever it is carrying (the live load). The forces of load and gravity, which would otherwise send a bridge sliding downhill, are used to hold an arch bridge aloft instead.
An arch bridge works by channelling gravity’s downward force into the structure’s centre — toward a central stone known as the keystone — rather than straight down.
Compression is the principle that allows the arch below to support the surface, or deck, above it.
Temperature changes can destabilise fixed arch bridges, hence the arch design is occasionally changed with hinges at each base and even the span’s centre.
This allows longer arch bridges to adjust to material expansion and contraction when temperatures fluctuate.
The beam bridge was the first form of bridge ever created due to its simplicity. It is still the most cost-effective to construct. All you need is a crossbeam that spans the gap and is supported at each end by an abutment. A girder bridge is a form of beam bridge that uses steel girders for reinforcement.
beam bridge
Gravity presents a greater issue when creating a bridge since, unlike a building, the majority of the space beneath it is empty.
To resist gravity and bear the full load, a beam bridge might be supported merely by two abutments, one at each end.
But there’s a catch with beam bridges: the longer a bridge is and the more people, cars, and other objects it carries, the heavier the entire weight becomes.
The more abutments on a beam bridge are spaced apart, the less stable the structure becomes.
You may make a long, stable bridge by putting supports in the middle, known as piers or stanchions, and connecting sections between them.
The Yolo Causeway in Sacramento, California, is 3.2 miles long, and the Lake Pontchartrain Causeway in Louisiana is 24 miles long.
The force of compression drives the weight inward onto piers in the middle of the bridge in beam bridges.
Simultaneously, the tension pulling or stretching force pulls the load outward toward the bridge’s abutments on both ends.
This design uses a vertically anchored pillar to support a horizontal deck that extends out from one or both sides across the span.
Both the above and below are frequently used to support the load.
A good example of cantilever construction is a diving board or platform.
cantilever bridge
Suspension Bridge Types
Suspension bridges are exactly what they sound like: they’re supported by vertical pillars or pylons that are linked by suspension cables.
Suspension bridge
Smaller, vertical suspenders are attached to these main cables and use tension to hold the bridge deck up.
Tension is the main force that sustains these types of bridges.
Despite the fact that the original suspension bridges were composed of simple ropes supporting wooden planks, the suspension technique now allows for vast spans across wide canals.
However, because these bridges are only attached to the ground in a few locations, they might shake when heavy traffic passes beneath them.
Vibrations can be caused by wind or movement across a bridge.
When these reach a specific frequency, resonance occurs, which is the same mechanism that causes the glass to shatter when a trained vocalist hits a high enough note.
Bridge crossings can be disrupted and collapsed if vibrations are strong enough.
Torsion, a twisting force commonly generated by external variables such as wind, can also impact these bridges, causing unsafe movement.
Travelers can be thrown off a bridge if the surface twists significantly while they are on it.
While torsion causes tension in a vertical plane, shear causes stress in a horizontal plane.
It occurs when opposing environmental pressures act on a single, fixed component of a bridge, causing it to break like a stick between two hands.
The load on a truss bridge is distributed across a succession of tiny sections that are joined together.
Bridge trusses are typically formed by structural beams for smaller bridges or box girders for bigger bridges, and are joined in a sequence of triangles by welded or riveted joints.
The bridge is held up by tension from vertical steel or timber supports, while compression from diagonal truss supports adds stability by directing the weight toward the centre, similar to an arch.
Truss bridge
That’s it about the main types of bridges. Each of these has advantages and disadvantages. We need to decide on the type of bridge based on the requirements.
Let me know in the comments if you need any further information.
Activated Sludge Process is a globally used wastewater treatment technique. In the previous blogs, I had shown you the various secondary wastewater treatment techniques. In this blog, we will dig deep into this widely used technique of activated sludge process, its configuration, process control and aeration methods.
The activated sludge process is a type of wastewater treatment that uses aeration and a biological floc made up of bacteria and protozoa to clean sewage or industrial waste waters. It is a biological process that finds applications in a variety of purposes, including oxidising carbonaceous biological matter and nitrogenous waste in the biological matter (mostly ammonium and nitrogen).
The activated sludge process employs aerobic microorganisms that can digest organic substances in sewage. Also, they have the ability to cluster together via flocculation. The flocculated particles settle out as sludge. As a result, the liquid coming out is relatively free of suspended solids and organic matter.
Activated Sludge Process Basic Configuration
The configuration of an activated sludge process for eliminating carbonaceous pollution consists of the following:
Aeration Tank: Air or oxygen is introduced into a mixture of primary treated sewage or wastewater combined with microbes (mixed liquor) in an aeration tank.
A settling tank: It is also known as a “secondary settling tank”. It separates biological sludge by allowing biological flocs to settle. A part of the sludge goes back to the aeration tank while the other for disposal.
Sludge Recycling System
Now, how about looking deep into what happens inside an activated sludge process?
Activated-sludge-Process – Flow diagram
Activated Sludge Process Steps
After primary treatment, wastewater enters into an aeration tank. A portion of sludge from the secondary settling tank also enters.
Organic matter comes into close contact with sludge from the secondary settling tank. Sludge is densely populated with microorganisms that are actively growing.
Diffusers or surface aerators inject air in the form of bubbles into the sewage-sludge mixture.
Microorganisms break down organic matter into stable chemicals like NO3, SO4, and CO2 while also producing new bacterial cells.
The effluent along with the actively growing microbial population passes to the secondary settling tank.
The secondary settling tank separates the aeration tank’s effluent, which contains flocculent microbial matter into supernatant and sludge. The treated supernatant undergoes further treatment before discharge.
This sludge from the settled waste returns to the aeration system’s inlet to re-seed the new wastewater reaching the tank. Return activated sludge (R.A.S.) is the fraction of the floc that returns to aeration tank.
The remaining sludge goes to sludge digesters for further treatment and safe disposal.
“Mixed liquor” refers to the combination of the liquid and microorganisms in the aeration tank. The suspended solids are called “Mixed Liquor Suspended Solids” (MLSS).
In the next section, we will find out the basic process control parameters in an activated sludge process.
activated-sludge
Process Control in Activated Sludge Process
The general process control method monitors the following variables:
Sludge Volume Index (SVI)
Mean Cell Residence Time (MCRT)
Food to Microorganism Ratio (F/M)
Dissolved oxygen (DO)
Biochemical oxygen demand (BOD)
Chemical oxygen demand (COD)
Let me explain these parameters in detail.
Sludge Volume Index
Sludge Volume Index is the volume of settled sludge in milliliters occupied by 1g of dry sludge solids after 30 minutes of settling in a 1000 milliliter graduated cylinder. It gives a measure of the settling ability of the sludge. SVI ranges from 40 to 100 for a good sludge which settles down easily. Bulking Sludge is a biomass consisting of filamentous organisms with very poor settling characteristics. For a bulking sludge, SVI value can exceed 200. Sufficient pH control, adequate aeration and addition of hydrogen peroxide to the aeration tank prevents bulking.
Mean Cell Residence Time
Mean Cell Residence Time is the ratio of total mass (lbs) of mixed liquor suspended solids in the aerator and clarifier to the mass flow rate (lbs/day) of mixed liquor suspended solids leaving as final effluent.
Food to Microorganism Ratio
Food to Microorganism Ratio is the amount of organic matter fed to the microorganisms each day relative to the mass of microorganisms under aeration. In other words, it is the ratio of the amount of BOD fed to the aerator (lbs/day) and the amount (lbs) of Mixed Liquor Volatile Suspended Solids (MLVSS) under aeration.
Main Control Parameters
The mean cell residence time and F/M Ratio are the main control parameters used industrially since both are directly related to the effluent quality. However, it is tedious to control the plant on the basis of the F/M ratio since it necessitates a lot of laboratory work to find the BOD and MLSS in the system. Therefore, the mean cell residence time is the best choice for controlling an activated sludge system.
Now you got an idea about the entire process and its important parameters. Next, we move on to the various aeration methods.
Aeration Methods in Activated Sludge Process
The decomposition of organic waste requires a very high concentration of oxygen at the initial stages of contact between microorganisms and the organic matter. The conventional systems usually maintain a plug flow hydraulic regime and keeps aeration and a mixing at an uniform rate along the entire tank. As a result, the oxygen concentration drops rapidly in the inlet and this can harm the microbes.
At the outlet, there is a surplus of oxygen which is not necessary and leads to economical losses. In order to match the oxygen supply and demand along the entire journey of wastewater from inlet to outlet, the mode of aeration needs some modifications. Let’s have a look at the different aeration methods in an activated sludge process.
Diffused Aeration
Sewage liquor is pumped into large tanks with floor-mounted diffuser grid aeration devices. Passing air creates a curtain of bubbles that oxygenates the liquor while also mixing it. An air blower usually creates the air. Oxygen replaces air for unusually strong and difficult to treat sewage.
Diffused aeration
Tapered Aeration
The organic waste needs more oxygen at the inlet. As it degrades progressively its oxygen demand decreases. Tapered aeration works on this principle. Aeration is intense at the inlet and decreases progressively along the length of the aeration tank. As this method involves the more efficient use of air, it results in savings in the pumping costs too.
Step Aeration
This method aims to equalize the oxygen supply and its demand. It introduces fresh feed at several points in the aeration tank, while keeping the rate of oxygen supply constant. This ensures a more even oxygen distribution over the entire tank and throughout the aeration stage. Baffles divide the aeration tank into several channels with each channel representing one step of the process.
Complete Mix Activated Sludge Process
In complete mix process, the aeration tank receives a mixture of fresh feed and recycled sludge at several locations within the tank. This ensures a constant supply and demand of oxygen along the length of the tank.
Contact Stabilisation
The microbial mass comes in contact with wastewater for short durations of time, approximately 0.5 to 1 hour in the biosorption unit. An anaerobic digestion unit stabilizes the resulting sludge after a retention period of about 2-3 hours. In the digestion unit, microbes consume the organic wastes removed in the biosorption unit. Since we stabilize the return sludge with higher solid concentrations, this reduces the volume of the aeration tank.
Pure Oxygen Activated Sludge Process
This type of activated sludge process supplies and recirculates pure oxygen in place of air into well mixed and converted chambers. Instead of the 5-10% oxygen utilization in conventional processes, the pure oxygen activated sludge process ensures about 90% utilization of oxygen. Further, it results in higher bacterial activity, lower sludge volume and sludge with better settling characteristics.
That’s it about activated sludge process. Let us know in the comments if you wish to know more.
The cloverleaf interchange is one of the attractive innovations in civil engineering. A cloverleaf interchange is a two-level interchange at which left turns are done by ramp roads (reverse directions in left-driving regions). It is not only aesthetically pleasing but also provides several advantages to the transportation system.
A cloverleaf interchange is a two-level interchange at which left turns are done by ramp roads (reverse directions in left-driving regions).
Vehicles first proceed to go left (in right-hand traffic) as one lane crosses over or below the other. Then, exit right onto a one-way three-fourth loop ramp (270 °) and merge onto the intersecting road.
The purpose of a cloverleaf is to allow two highways to cross without the need for any traffic to be stopped by red lights, except for the left and right turns.
Traffic weaving is the limiting factor in a cloverleaf interchange’s ability.
In the next section, let me take you through some examples of clover leaf in India.
So, you got an idea about clover leaf roads. Let me quickly walk you through the major challenges and problems associated with this.
Cloverleaf interchanges – Main problems and challenges
Clover leaf interchange top view
The biggest downside of the cloverleaf’s classic configuration is that at the end of a loop, vehicles converge on the highway immediately before other vehicles exit to go around another loop, causing a dispute known as weaving.
Weaving restricts the number of traffic-turning lanes.
Since then, the majority of road authorities have adopted new interchange designs with less-curved exit ramps which do not lead to weaving.
These interchanges include diamond, parclo and single-point urban interchanges (SPUI) when connecting at the crossroads to an arterial road in non-free-flowing traffic and the stack or clover and stack hybrids when connecting in free-flowing traffic to another freeway or to a busy arterial where signals are not yet needed.
Upgrades for cloverleaf interchanges
For new interchanges, not only are these ideas valid, but they also hold when existing cloverleaf interchanges are upgraded.
The exchange between US 13 and US 58 was originally a cloverleaf in Norfolk, Virginia; it has since been turned into a SPUI.
In addition, several cloverleaf interchanges are being upgraded to parclos on California freeways, such as U.S. 101. In Hampton, Virginia, a cloverleaf interchange was partly unwound into a partial stack interchange between Interstate 64 and Mercury Boulevard.
As part of a major highway improvement project to upgrade the highway to Interstate standards, four cloverleaf interchanges along I-64/US 40 in St. Louis, Missouri, were substituted with SPUIs between 2008 and 2009.
Adding a collector/distributor route next to the highway is a compromise; this does not prevent weaving but takes it off the main lanes of the freeway. An example of this is the Sheboygan, Wisconsin, State Highway 23/Interstate 43 interchange, where the exit/entrance roads on and off Highway 23 are two lanes on the north and southbound sides of the road next to the main I-43 freeway.
Traffic signals in leu of cloverleaf interchange
Several cloverleaf interchanges on the non-freeway route have been removed by installing traffic signals.
This is also done sometimes at the intersection of two freeways, particularly when one freeway ends at an interchange with another.
An example of this is at the intersection between Interstate 5 and Washington State Route 512 in Lakewood, Washington, where a noticeable ramp stub reveals that one of the four leaves has been cut, thus removing weaving on I-5.
The traffic signal will be replaced by a two-lane flyover in the future, again completing the freeway-to-freeway interchange.
Cloverleaf exchanges often appear to consume much more land than any other form of exchange (with the possible exception of stack interchanges).
Numerous cloverleaf intersections include the merging of traffic from the clover directly into the collector/distributor lane in the Lower Mainland of British Columbia, Canada.
This allows the slowly moving driver to merge around the loop ramp with the rapidly moving driver leaving the collector/distributor lane without the ability to accelerate to balance the oncoming driver’s flow.
This merging velocity gap can be as high as 65 km/h (approx. 43 mph).
In the United Kingdom, owing to these performance concerns, the cloverleaf interchange was not introduced in significant numbers. Originally, there were three, one in Redditch and two in Livingston.
In Ontario, most cloverleaf interchanges have been phased out, but with similar traffic patterns, some near variants remain.
However, the key difference is that single bidirectional carriageways share the adjacent on and off-ramps.
Examples include the intersection in Belleville, Ontario, between Highway 62 and Highway 401, as well as the interchange in Toronto between Lawrence Avenue and Don Valley Parkway.
So, how was the trip through the clover leaf interchange? Let me know in comments, if you have any queries.
Component of a bridge/ bridge components plays a very important role in maintaining the stability and functional requirements of the bridge structure. Each bridge component has its functions. The bridge component types and functions vary as per the site conditions, design requirements, and functional requirements. This article is about a total overview of the components of bridge/bridge components.
A bridge is a structure built over physical obstacles such as water bodies like rivers, lakes, canals, etc, and valleys, roads, etc with minimal obstructing to the area below. During ancient times bridges are made by falling of trees, providing stepping stones, and by tying a rope from the trees. Bridges are the most important components of a highway, railway, and urban roads. Brides play an important role in the socio-economic, politics, culture, defence, etc of a region and a country.
The components of the bridges are divided broadly into ..
Components of a bridge
a) Sub- structure
c) Super structure or decking component
Components of a bridge below the bearing constitute substructure and components above the bearings constitute superstructure or decking components.
You tube video – Components of a Bridge
VIDEO SHOWING BRIDGE COMPONENTS/COMPONENT OF A BRIDGE
Bridge components – Substructure
The main function of the substructure is to support the superstructure components and transfer the loads to safe strata. The major substructure components of a bridge are as follows.
Abutments functions as vertical supports to the superstructure components at the bridge end. They are the endpoints of a bridge and acts as an approach for the roadway. Abutments retain the roadway backfill and base materials and act as lateral support to the embankments approach. Because of these properties, the abutments are designed as retaining structures.
A single span bridges got two abutments which serves as a vertical support and lateral support. Abutments also resist lateral movement of earth fill of the road approaches.
components of abutment
Abutment are of various types depending on the design requirements and load considerations.
Cross section of abutment
Types of Abutments
Closed Abutment
Stub or Perched Abutment
Pedestal or Spill-through Abutment
Integral End Bents
Mechanically Stabilized Abutment
Wing walls and return walls
Wing walls are located near to the abutments as an extension of abutments or as independent structures. They act as a retaining wall to resist the earth in the approach areas. Wing walls may be placed right-angled to the approach way or splayed as shown in the figure.
Piers
Piers are intermediate vertical supports provided between bridge spans. The main function of a pier is to transfer the loads coming on the superstructure to the foundations. Pier got pier caps to provide sufficient bearing areas for the transfer of superstructure loads.
Piers are basically compression members and are designed for vertical loads but in high seismic areas they are designed for lateral loads also.
piers
Foundation
Foundations are constructed to transfer loads coming on the superstructure and substructure to a larger area and hard strata. The foundations may be an open foundation or pile foundation or some other foundation type depends upon nature or soil strata and design considerations. The foundation has to be provided at sufficient depth to ensure protection and chances of failure against the scouring and undermining process.
Component of a bridge – Super structure or decking components
The superstructure constitutes deck slabs, deck beams/girders, trusses, cables, arches, handrails, parapet, etc. The superstructure components depend on the type of bridge-like concrete, composite, steel, etc. The following are the basic superstructure components.
a) Bearings
b) Bridge deck
Bridge bearings
Bridge bearings are components of the bridge that provides a resting surface between the bridge pier and the bridge deck. The main function of the bearing is to control movements and reduces the stresses involved.
A bridge bearing carries the loads or movement in both vertical and horizontal directions from the bridge superstructure and transfers those loads to the bridge pier and abutments. The loads can be live load and dead load in vertical directions, or wind load, earthquake load, etc., in horizontal directions.
bearing
Decking components
Decking is the surface over which the traffic like road or rail passes. The decks are supported on beams, girders (prestressed or post-tensioned ) viaducts, prefabricated segments, steel girders or hanged through cables. The whole decking components are supported by pier which transfer the loads to reliable soil strata.
The deck beams shall be conventional rectangular type or of I – GIRDERS (Concrete or steel)
Types of Deck support beams
The surface of the deck may be of the concrete or bituminous for movement of traffic.
SUPERSTRUCTURE COMPONENTS OR DECKING
There are a lot of miscellaneous components like strip seal expansion joints which separates the deck spans, Hand rails are provided on the deck side as a barrier and protection.
Construction has always been about the speed and efficiency that can be ensured with the materials and techniques of construction. Prefabrication is an amazing technology that helps to reduce time and have many more benefits.
In this blog, we will find out all the details about the same.
Prefabricated construction, or “prefab,” is a method of construction that uses components made off-site in a factory, which are then transported put together on-site to create a structure.
With different advantages to offer, there are a few different common types of prefab. You may want to consider incorporating any of these solutions, depending on your particular building project.
So, that’s the basic details. We will discuss about the benefits in next section.
It is already difficult for contractors to find labour, but construction still needs to take place.
It decreases labour productivity much more as on-site building continues piecemeal.
Therefore, prefabrication helps businesses speed up timelines, make the most of their on-site labour, improve efficiency, and succeed in the marketplace.
It also costs less to transport partial assemblies from a factory than to move pre-production resources to each site.
Plus, as labour efficiency increases, personnel-related costs decline.
Time savings:
Time is the essence of the rainy season, and prefabrication will help you manage tighter timelines.
Quality control:
Factory tools can provide added quality assurance as opposed to repetitive construction on-site.
In addition, consistent factory indoor environments remove much of the weather effects on manufacturing, while streamlined manufacturing and production improve job site safety on the whole.
Accelerated offsite production of parts results in reduced emissions and work disruption.
This preserves wetlands or protected areas nearby and minimises local flora and fauna disturbance.
The controlled, dry environment of modular construction saves water consumption and allows scrap and other materials to be recycled.
Plus, fossil fuel consumption plummets with less on-site traffic and streamlined transportation.
Better safety and security:
By reducing a construction site’s timeframe, you simultaneously decrease the amount of time that the site is vulnerable to vandalism or robbery.
Flexibility:
It is easy to disassemble and move modular construction to various sites.
This greatly decreases the demand for raw materials, minimises the resources spent and overall reduces time.
Modular construction also allows for versatility in the structure’s design, allowing for an infinite number of possibilities.
Since prefabricated building units can be used in various spaces, their neutral aesthetics can be combined with almost any form of construction.
Reduced Site Disruption:
There is much fewer truck traffic, machinery and material suppliers around the final construction site as several parts of a building are completed in the factory.
The disturbance of conventional workplaces suffering from noise, emissions, waste and other common irritants is therefore minimal.
This structured design approach offers a much more productive productivity environment and removes unwanted disruptions and interruption typical of construction sites.
Time to know the challenges of prefabrication.
Challenges of Prefab Construction
Construction site of prefabricated building
The joints to be given should be well-built enough to convey all sorts of stresses, connecting the core structure and the components.
The strength and solidity of the whole building totally depend on the strength of the joint.
Therefore, rather than component-based analysis, it is important to have detailed studies on the whole system.
One of the key challenges in embracing prefabrication technology in construction requiring accuracy and precision is the need for skilled labour on-site and the lack of on-site automation.
Skill development and native automation are also mandatory for prefabricated systems to be installed.
It is likely to get damaged during the erection or transport of heavy machinery units, so the arrangement of the units must be performed precisely and this process in a congested area becomes sloppy.
Labour maintenance is another concern because prefabricated construction requires skilled labour as it differs from in-situ construction, which requires machine-oriented expertise both on-site and in the production process.
Now, let me show you the advantages of prefabrication
Advantages of Prefabrication
Prefabrication technology has several advantages, such as energy efficiency revision, minimal waste and inspection, efficient construction, work speed, protection, sustainability and quality.
As self-supporting ready-made components are used, the need for formwork, shuttering and scaffolding is substantially lowered.
Building time is thereby decreased, resulting in lower labour costs.
Reduced the quantity of waste materials relative to building on site.
Reduction in construction time to allow an earlier return of the invested principal.
Construction guarantees precise compliance with building codes and excellent quality assurance.
Along with quality control and factory sealing, high-energy performance.
It is possible to place prefabrication sites where skilled labour is more readily accessible and the costs of labour, electricity, materials, space and overhead are reduced.
Prefabrication permits building throughout the year, regardless of the weather (related to excessive cold, heat, rain, snow, etc.).
Material waste from the building is less.
Regardless of climatic conditions.
Security and worker comfort levels are higher in the off-site building.
Last, but not the least the disadvantages should be known.
Disadvantages
Material assembly for prefab construction
The subsequent constraints are known to have restricted design choices, decreased reselling value, high initial expenditure, non-suitability for foundation and precast unit transport.
There are even more drawbacks. They are the following:
Leakage occurs in joints in prefabricated parts.
For huge prefabricated parts, transportation costs can be high.
To ensure affordability through prefabrication, increased production volume is required.
Initial costs for construction are higher.
The initial production of designs is time-consuming.
Large prefabricated parts require heavy-duty cranes and measurement of precision from handling to position on site.
Local employment can be lost, as skilled labour is needed.
Modular building design and construction requires high levels of cooperation between project parties, particularly architects, structural engineers and manufacturers.
These buildings usually depreciate more rapidly than standard site-built housing due to their shorter economic existence.
Hope the time you spent for the article was worth it. Let me know if you have any doubts in comments.
Anchored retaining wall system is a structural element installed through the rock or soil to transfer the tensile forces developed in the structure to the ground. Anchored retaining walls are often slimmer than all their counterparts like gravity walls and cantilever retaining walls.
Anchored retaining wall or Tie back system – Installation method.
Anchored retaining wall is also known as a tie-back system. They are used in combination with cantilever retaining walls, piled retaining walls, sheet piles, tangent walls, etc. The Tie-back system enhances the stability of the structure and plays an important role in equipping the walls to handle additional loads.
The anchored walls are installed when the load acting on the structure is high. In this case, the design of cantilever retaining walls / piled retaining walls/ sheet piles etc seems uneconomical. Moreover, it is difficult to accommodate the foundation and structures due to space constraints. For enhancing the load-carrying capacity and economising the structure additional anchors are embedded in the earth to be stabilised. These anchors in combination with the main structure negotiate the loads.
One end of the tieback is anchored to the wall and another end is driven to the soil/rock. Sometimes stable concrete structures are driven into the ground to get a good anchorage. Tiebacks and drilled through the wall to the soil at an angle of around 15-45 degrees.
After drilling the holes ties or struts are provided inside the drilled holes and pressure grouted to give greater stability. In the case of piled retaining walls, the tie-back system is drilled through whaler beams installed between the piles as shown in the figure. Steel rods are placed inside the drilled holes and grouted under high pressure. This creates a bulb-like anchor at the rods’ end, preventing the tie-backs from pulling out the load.
Waler system used for anchoring
These walls can be very tall and support high loads and are ideal for smaller areas that need earth retention.
Some times instead of rods, helical anchors are also driven to in place and the capacities are decided by the torque required for tightening the anchors.
Helical anchors
The main purpose of the tieback system is to develop a strong soil mass to resist external failure modes. The moment of soil and wall has to be restricted to get better serviceability.
Advantages of anchored retaining walls
Mostly used for slope protection and retaining earthworks of deep excavations.
Thin walls or very light structures can be designed in combination with anchored walls.
Anchored walls are one of the most economical systems of earth retention.
Combination with sheet piles, cantilever retaining walls, piled retaining walls etc are very useful for deep excavations to provide a safe working area.
For more details about the retaining walls watch the below video.
Youtube video – 15 Types of Retaining wall systems
Types of Gauges in railway is a mandatory topic to touch upon when you study railway engineering. In this article, I will take you on a journey through the three basic types of railway gauges: broad gauge, metre gauge, and narrow gauge.
The gauges in railway is defined as the clear minimum perpendicular distance between the inner faces of the two rails. The distance between the inner faces of a pair of wheels is called wheel gauge.
The figure below is a diagrammatic representation of gauges in railway.
Gauges in railway
Now, let’s jump right on to the various types of gauges in railway.
I will tell you more details about each of them in the upcoming sections. Let’s start with broad gauge.
Broad gauge
When the clear horizontal distance between the inner faces of two parallel rails forming a track is 1.676m, the gauge is called broad gauge. Also known as standard gauge in some countries.
Broadest gauge is used for tracks in plain areas which are densely populated for routed of maximum traffic at places which are centers of industry and commerce.
Suitability: Broad gauge is suitable under the following conditions
When sufficient funds are available for the railway project
When the prospects of revenue are very bright
So, you got an idea about broad gauges. Let’s look into metre gauge now.
Metre gauge
Metre gauges are used when the clear horizontal distance between the inner faces of two parallel rails forming a track is 1m. It is used for tracks in under- developed areas and in interior areas where traffic intensity is small and prospects for future development are not very bright.
Suitability: Metre gauge is suitable under the following conditions;
When the funds available for the railway project are inadequate
When the prospects of revenue are not very bright.
That’s it about metre gauge. Next, let me give you some information about narrow gauge.
Narrow gauge
Narrow gauge is leveraged when the clear horizontal distance between the inner faces of two parallel rails forming a track is either 0.762m or 0.610m. These are used in hilly and very thinly populated areas.
Suitability: Narrow gauge is suitable under the following conditions:
When the construction of a track with wider gauge is prohibited due to the provision of sharp curves, steep gradients, narrow bridges and tunnels, etc.
When the prospects of revenue are not very bright.
You have seen all types of gauges in railway. Did you know the factors that should be taken into account while selecting a gauge? Its time to see that.
Factors affecting the choice of types of gauges in railway
Railway track
Traffic condition: If the intensity of traffic on the track is likely to be more, a gauge wider than the standard gauge is suitable.
Development of poor areas: The narrow gauges are laid in certain parts of the world to develop a poor area and thus link the poor area with the outside developed world
Cost of track: The cost of railway track is directly proportional to the width of its gauge. If the fund available is not sufficient to construct a standard gauge, a metre gauge or a narrow gauge is preferred rather than to have no railways at all
Speed of movement: The speed of a train is a function of the diameter of wheel which in turn is limited by the gauge. The wheel diameter is usually about 0.75 times the gauge width and thus, the speed of a train is almost proportional to the gauge. If higher speeds are to be attained, the broad gauge track is preferred to the metre gauge or narrow gauge track.
Nature of country: In mountainous country, it is advisable to have a narrow gauge of the track since it is more flexible and can be laid to a smaller, radius on the curves. This is the main reason why some important railways, covering thousands of kilometres, are laid with a gauge as narrow as 610mm
Gauge should be uniform and correct: Uniformity of gauge is necessary due to the following reasons:
Inconvenience to the passengers while changing the train at the station, with the change of gauge:
Delay in the movement of people and goods resulting in wastage of time
Extra labour for unloading and reloading the goods
The goods are also likely to be damaged or dislocated at the junction station, having a change of gauge.
Provision of extra and costly yards, godowns, sheds, etc. At every junction station having a change of gauge. Difficulty in quick movement of military and equipment during war days.
So, you got to know everything about gauges in railways? Did I miss out anything? Let me know your thoughts in the comments.
Classification of roads or Types of road is an important topic in transportation engineering. It varies with different parameters. Let’s go through the important types of roads every civil engineer should know. We will see important details about cement concrete roads and types of road surface through the course of journey.
These are the cheapest type of road and is used at the places where traffic is rare. The type of road surface used in these roads is soil. The pavement structure is totally made up of soil available at site. The performance of these roads mainly depend upon the effective maintenance and proper drainage.
Gravel roads
These are intermediate between earthen and metalled roads. The carriage way of these roads is made by compacting a mixture of gravel and earth. These type of road surface usually consists of 26 percent sand, 13 percent clay and 61 percent gravel.
Kankar roads
The type of road surface used in this classification of roads is Kankar. Kankar is impure form of limestone. Hard variety of kankar may be as strong as stones, but soft variety may be very weak. The road having pavement layer of kankar are termed as kankar roads. Traffic capacity of this type of road depends on the type of kankar used.
Moorum roads
In this type of roads, Moorum is the material used for building the road. Moorum is obtained due to disintegration of igneous rocks by weathering agencies. In this road, the surfacing of the traffic way is constructed from Moorum. These type of roads are low and is equivalent to gravel and Kankar road in performance.
Water bound macadam roads (WBM roads)
The broken stones of base and surface course, if any are bound by the stone dust in presence of moisture is called WBM rods. Total thickness may vary from 7.5 to 30cm depending upon the traffic.
Bituminous roads
Most of the roads around the world are constructed by using bitumen. It is also called flexible pavement because it changes according to nature of loads and sub base. This is an important member in the types of roads in India. For the road construction, the major concerns, as with concrete, are cost and durability.
Applications of bituminous roads
Highways
Express ways
Runways
Now, let’s meet cement concrete roads.
Cement concrete roads types – Most durable classification of road
Cement concrete roads are the roads whose wearing surface is constructed with cement concrete. They are otherwise called concrete roads. They can be constructed either reinforced or plane type. Cement concrete roads are compatible to all weather conditions. It comes under rigid pavements. These are best suitable to roads having higher traffic.
Main applications of cement concrete roads
Parking aprons, taxiways and runway take off areas in airports
Parking grounds for vehicles of heavy weight
Heavy duty Industrial floors (vehicles on tracks and military tanks)
Floors for handling and storage of containers at ports
Industrial floors with high requirements in terms of flatness and durability to abrasion and surface exposure to aggressive attacks (use of toxic materials, welding etc)
Bridge decks
Road pavements in long tunnels for fire safety reasons, immediate reuse of the road following a fire and better energy consumption during service life (lower intensity lighting required)
Pavements at toll stations (resistance to braking and acceleration)
Now, let’s move on to the next classification of roads.
Classification of roads according to location and function
Roads can be classified according to the location and function as follows.
National highways
Highways
District roads
Village roads
Going deep to each of them,
National highways- top member in classification of roads according to location
Main highway runs through the length and breadth of the country. Roads connecting the neighbouring country. are also called national highways. Roads connecting the neighbouring countries are also called national highways. It should have high class surface finishing together with adequate structural strength.
Highways
These are the main roads within a state. These connect important towns and cities of the state. Highways should be two lane wide, but if it is one lane only, it must be provided with wide shoulder.
District roads
These roads should carry the traffic to the interior rural areas. These roads are considered as main branches from NH or SHs. District roads are of 2 types. Major district roads and other district roads.
Village roads
These roads are mainly meant for village roads use. These connect villages with each other and also with nearby towns. These roads can be stabilised each roads, but if metal surface is provided it can serve more useful purpose.
Moving on to the third classification…
Classification of roads based on number of lanes
You might have observed this type of classification while you travelled. There are mainly 4 types as given below.
Single lane road- having only one lane for to and for mobility.
Double lane road- having two lanes for direction to opposite sides
Three lane road- having three lanes for movement in a road
Multi lane road- having more than three lanes for vehicle movement.
The decision on which of the above lanes is to be chosen is based on the traffic.
The next classification of roads is based on the geographic location of the roads.
Types of roads depending on weather
These are of 2 types.
All weather roads- Roads which are compatible to all weather conditions. Types of roads in India should mostly belong to this type. Because the weather conditions are extreme.
2. Fair weather roads- Roads which are not compatible to worse weather conditions.
Next is an interesting classification based on the geometry of roads.
Types of roads based on Road pavement type
Parallel roads- These are local roads running parallel to a higher-speed, limited-access road
Unparallel roads- These are local roads that don’t run parallel to a higher speed and limited access road. The village roads that connect small geographical places best fit for this classification other than other types of roads in India.
Cool. Let’s jump into the last classification of a road.
Types of roads according to the volume of traffic they handle
Roads can be classified depending on the traffic through it.
Light traffic road- Road carrying up to 400 veh/ day
Medium traffic road- 400- 1000 veh/day
Heavy traffic road- More than 1000 veh/day
That’s it. Any doubts or comments? Drop it in the comments. Let’s dwell on more.
The Properties of Aluminium play an important role in its transformation to one of the most significant and versatile materials on earth. The properties of aluminium are acquired from its ability to form aluminium alloys on combining with chemical elements. These aluminium alloys got unique properties that can be customised for various applications. Aluminium sections are available in various forms that include aluminium square bars, aluminium plates, aluminium extrusions etc.
What is aluminium?
Aluminium is a silvery-white lightweight material that makes up for more than 8% of the earth’s core mass. It is the 13th element of the periodic table. and is the third common element on earth other than silicon and oxygen. Aluminum is available in the form of aluminium sulphates.
ALUMINIUM PROCESSED IN SMELTERS
Manufacturing process of aluminium
The primary raw material used for producing aluminium is Bauxite. Extracting a tonne of aluminium requires 5-6 tonnes of bauxite. Aluminum is manufactured in two phases: the Bayer process of refining the bauxite ore to produce aluminium oxide. Aluminium oxide is processed in smelters to produce aluminium. The process of extraction of aluminium from bauxite is known as electrolysis or electrolytic reduction.
ALUMINIUM SMELTER
Properties of aluminium.
Aluminum is one of the most commonly used building material. Aluminum is the preferred choice for a lot of applications because of its unique and valuable properties.
a) Light weight properties of aluminium
Aluminium is lightweight and is 1/3rd the weight of steel and is one of the lightest materials in the world. Even though aluminium is lightweight it is very strong and corrosion-resistant. Because of its lightweight properties, aluminium can reduce the dead loads on a structure and optimise the design. This optimisation can reduce costs in a lot of applications.
b) Corrosion Resistant properties of aluminium
Aluminum is corrosion-resistant, due to the formation of a thin oxide film on its surface. This film acts as a barrier and prevents corrosion.
c) Non magnetic properties of aluminium
Aluminum is non-magnetic and a very good conductor of heat and electricity. Because of these properties aluminium is used for power transmission cables, computer components, LED lights, etc
d) Flexibility in moulding and fabricating
Aluminum is processed in both cold and hot conditions. It can be easily pulled, moulded, rolled, and extruded very easily. Similarly, aluminium can be formed into thin sheets of even 4-micron thickness. They can be welded and fabricated to any shape. Aluminum is used for making sophisticated aircraft parts to foils for wrapping. Considering the flexibility of fabrication into any shape aluminium forms an integral part of the construction sector for facades, skylights, green building structures, doors, and windows, etc
ALUMINIUM GLASS HOUSE
e) Aluminium alloys
Aluminum forms a huge variety of alloys in combination with a lot of chemical elements. Even the smallest change in the percentage of ingredients can change the metal properties. This gives the much-needed flexibility for usage in various conditions. Aluminum zinc alloy is used for making computer and mobile components, similarly aluminium with silicon is used for manufacturing alloy wheels and automobile components. A small percentage of elements can vary the properties to any extend.
f) No toxic and odourless
Aluminum is non-toxic and orders less. Hence it is used extensively in the food processing and beverage industries.
g) Strength at low temperatures
Aluminum can retain its strength even at very low temperatures wherein steel tends to get brittle in low temperatures.
h) Coating/painting
Aluminium can be coated/finished using any colour in line with the objects colour scheme.
i) Recyclable
Aluminum is a hundred percent recyclable. The recycled product has all the qualities of a virgin product.
j) Reflective properties of aluminium
Aluminum posses very good reflectivity. Hence it is used for roofing sheets and Light shades. Aluminum roofing can reflect heat and cools the ambient temperature.
Applications of aluminium in construction sector
Aluminum can be welded, fabricated, painted, and moulded into any shape and forms. They are lightweight and can be lifted and erected very easily. Because of these unique qualities, aluminium is one of the most versatile, significant, and cost-effective materials used in the construction sector. The most important use of aluminium is in the form of extrusions. Aluminium is also available in form of aluminium square bars, aluminium plates etc. Extrusions are fabricated/jointed to form doors, windows, and partitions, frames of facades, skylight structures, green buildings, aluminium structures, etc. Aluminum extrusions are coated/painted to match the colour scheme of the building/structure. Because of these qualities, aluminium is the most popular material used extensively in the construction sector.
ALUMINIUM EXTRUSIONS FOR VARIOUS USES
Aluminium coatings
Aluminum itself is non-corrosive due to the formation of thin oxide films on the surface for protection from corrosion. Then why you need a coating for aluminum.
a) Enhance the look and appearance
Mill finished aluminium is dull in colour and may not always match with the building/structure’s colour scheme. On the application of the coating, the aluminium structures can match the colour scheme of buildings/structures. Designers/architects proposes the type of coating and colour to be applied after analysing the utilities, environment, and colour schemes. A coating matching with an appropriate colour scheme can enhance the appearance and look of structures/buildings.
b) Increase the Corrosion resistant properties
Most of the cases the oxide film on the surface of aluminium is sufficient to take care of corrosion. In some cases, the structures need an extra protection from corrosion. Similarly long exposure to moisture and water can damage the natural oxide film. The coatings can increase the thickness of oxide film and can provide an extra layer of protection which in turn enhance the protection against wear and tear, handling defects, and corrosion.
ALUMINIUM CLADDING
c) Hardness of members
Coatings can increase the hardness of the materials and protect the material from excessive wear and abrasion encountered on transportation, loading, fabrication erection, etc. Coatings also protect the structures against possible wear and abrasion when used in high traffic areas.
d) Dye marks
Mill finished aluminium have dye marks. Coatings cover these dye marks and makes the surface look smooth and even.
e) Reflectivity
Coatings increase the reflectivity of aluminium and hence used for roofing sheets and light covers.
ALUMINIUM CLADDING
Coatings and treatments on aluminium
The most commonly used types of coatings are as follows. The type of coating basically depends on the choice of colour, hardness required, durability and area of application. The following are the the three different types of coatings commonly used for aluminium.
Rainwater harvesting methods are the processes in which precipitation that falls on a site is diverted, captured, and stored for use on-site, as opposed to allowing it to run off, evaporate, or infiltrate into the soil. Let’s get to know it in the best way through the course of journey in the blog.
“Slanting silver ropes slammed into loose earth, plowing it up like gunfire”- When Arundhati Roy described the rain as beautifully like this, how many of us thought we are taking the boon of no cost from nature. It’s high time that we understood the worth of various rainwater harvesting methods in our lives.
Let’s start from scratch.
How rainwater harvesting methods are important?
This is a sad story of ground water. It all started with the over population. water supply agencies became unable to cope up demand from surface sources like dams, reservoirs, rivers etc. They resorted to ground water sources by digging tube-wells in order to augment the water supply. Indiscriminate exploitation of ground water resulted in lowering of water table rendering many bore-wells dry. To overcome this, we started to drill bore wells to greater depths. The exploitation of ground water in brutal unscientific methods by soft drinks, mineral water and similar industries further declined ground water table. The solution to all these problems is to replenish ground water bodies with water conservation like leveraging rain water by man made means.
That’s it. And we are here to know the hero of the story, Rain water to solve all these issues.
Let’s look at its components now.
Components of rainwater harvesting methods
Rainwater conservation is a must need element of every green building. Let’s see the components below.
1. Catchment area
The catchment area is the surface on which the rain water falls. This may be a roof top or open area around the building.
2. Coarse mesh / leaf screen
To prevent the entry of leaves and other debris in the system, the coarse mesh should be provided at the mouth of inflow pipe for flat roofs
3. Gutter
Gutter is required to be used for collecting rainwater from sloping roof and to divert it to downspout. These are the channels all around the edge of a sloping roof to collect and transport rain water to the storage tank.
4. Down spout or conduit
The rain water collected on the roof top is transported down to storage facility through down spouts / conduits. Conduits can be of any material like PVC, GI or cast iron.
5. First flushing device
A first flush system is incorporated in the rooftop to harvest rainwater by avoiding all the debris, dirt, and other contaminants especially bird dropping, etc. accumulated on the roof during the dry season. The first flushing device, dispose of the first spell of rainwater so that it does not enter the system.
6. Filter
The filter unit is basically a chamber filled with filtering media such as fiber, coarse sand and gravel layers to remove debris and dirt from water before it enters the storage tank.
7. Settlement tank
The settlement tank facilitates the settling down of suspended materials like silt and other floating impurities before the water recharge the aquifer.
8. Storage tank
Storage tanks are used when the water from the rain water harvesting is used directly for various purposes.
Okay. That’s done. Now we are getting into the important part which is how to make rainwater harvesting.
RAINWATER HARVESTING METHODS- DETAILED
1. Storing rain water for direct use
Fig. Storing rainwater for direct use
In place where the rains occur throughout the year, rain water can be stored in tanks However, at places where rains are for 2 to 3 months, huge volume of storage tanks would have to be provided. In such places, it will be more appropriate to use rain water to recharge ground water aquifers rather than to go for storage. If the strata is impermeable, then storing rain water in storage tanks for direct use is a better method. Similarly, if the ground water is saline/unfit for human consumption or ground water table is very deep, this is one of the best rain water harvesting methods that can be applied.
2. Recharging groundwater aquifers, from rooftop runoff
Fig. Recharging ground water aquifers from roof top run off
In this groundwater harvesting, rain water that is collected on the roof top of the building may be diverted by drain pipes to a filtration tank from which it flows into the recharge well. The recharge well should preferably be shallower than the water table. This method of rain water harvesting is preferable in the areas where the rainfall occurs only for a short period in a year and water table is at a shallow depth.
Alright. That’s it about second in the list of rainwater harvesting methods. How to increase groundwater level further?
3. Recharging groundwater aquifers with runoff from the ground area
Fig.Recharging ground water aquifers with runoff from ground areas
The rain water that is collected from the open areas may be diverted by drain pipes to a recharge dug well / bore well through filter tanks. The abandoned bore well/dug well can be used cost effectively for this purpose.
Now you have become a savvy in rain water harvesting methods. But this is not all. Even if you have completed all the procedures with at most care, precautions should be taken to ensure quality of water. Let’s see them.
1. Roof over which water falls, should be cleaned before rain fall.
2. The suitable type of first flushing device to be installed and initial 10 to 15 minutes of runoff should be diverted.
3. The water collected from roof top only, should be stored in storage tank for direct use.
4. The runoff from surface/ground should be preferably be used for recharging ground water aquifers after proper filtration.
5. The rain water collected from roof top should pass through suitable type of filter and only then it should be stored in storage tank / used for recharging ground water aquifers.
We are almost near of completion. its time to look at the results of your efforts.
Advantages of rain water harvesting methods are,
(a) Promotes adequacy of underground water
(b) Mitigates the effect of drought
(c) Reduces soil erosion as surface run-off is reduced
(d) Decreases load on storm water disposal system
(e) Reduces flood hazards
(f) Improves ground water quality / decreases salinity (by dilution)
(g) Prevents ingress of sea water in subsurface aquifers in coastal areas 6
(h) Saving rainwater improves ground water table, thus saving energy (to lift water)
(i) The cost of recharging subsurface aquifer is lower than surface reservoirs
(j) The subsurface aquifer also serves as storage and distribution system
(k) No land is wasted for storage purpose and no population displacement is involved
(l) Storing water underground is environment friendly
But all these doesn’t earn you a penny. Below are the points that illustrates how rain water harvesting methods can add to your pockets.
Energy savings
Rainwater collector systems are typically designed to be gravity fed.
Storage areas are typically lower elevation, so a pumping system is generally required for intended reuse.
Since collected rainwater is generally used close to its capture, the energy needed to convey the water tends to be minimal.
Compared to conveyance from other supplied sources of water rainwater harvesting methods would likely have lower energy costs.
Systems are simple and tend to be robust. Monitoring and maintenance require additional effort. This includes maintenance of roofs used as collection areas, cleaning of gutters, maintenance of storage tanks and vaults, puumps and maintenance of water treatment systems
Water savings
A reasonable goal for an aggressive rooftop collection for a custom building could be to reduce domestic water supply by 40 to 50% for that building; this would then allow the building to meet LEED goals for sewage reduction.
Well… limitations too are important to see if it’s worth trying.
Disadvantages of rain water harvesting methods are,
Unpredictable Rainfall
Initial High Cost
Regular Maintenance
Certain Roof Types may Seep Chemicals or Animal Droppings
Storage Limits
Now, it’s up to your decision on which of the above rainwater harvesting methods you want to adopt. But I would say this is an offer you can’t refuse.
Vincivil FAQ CORNER
What is the main purpose of rainwater harvesting methods?
The main aim of rainwater harvesting methods is to use locally available rainwater to meet water needs during the year without the need for major capital expenditure.
How to catch rainwater?
The rain would accumulate in the gutters that would funnel the water into the downpours and then into some kind of storage vessel. Rainwater collection systems can be as easy as gathering rain in a rain barrel or as complex as storing rainwater in large cisterns to supply your entire household demand.
How rainwater harvesting methods are done?
Rainwater harvesting methods extract the run-off from a building or other impervious surface to be preserved for later use . The rain would accumulate in the gutters that would funnel the water into the downpours and then into some kind of storage vessel.
How rainwater harvesting methods work?
Rainwater collection systems collect rainwater by transferring it from large surfaces to underground or overground storage tanks. The rainwater harvested is filtered and then pumped directly to the appliances or header tank.
What are the rainwater harvesting methods at home?
There are several techniques such as Storage of direct use, recharging groundwater aquifers, recharging of bore wells, recharge pits, soakway or recharge shafts, recharging of dug wells etc.
How do you make a rainwater harvesting pit?
Excavation is to be performed before soft dirt, weathered rock or fracture is reached. You need jelly of different sizes and sand at the top of the pit. The big jelly at the bottom creates large gaps for the water to pass through.
What are the two important rainwater harvesting methods?
Surface runoff harvesting and rooftop rainwater harvesting are the main two methods of rain water harvesting.
What are the main uses of rainwater harvesting methods?
Non-potable uses, such as toilet flushing, irrigation, dust control, and vehicle washing. Some of these applications may require specialized plumbing.
Potable water uses including drinking water, food preparation, showering, and washing.
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