Objective:
Main objective of literature review of the paper was to study the utilization of treated water or reclaimed water for use in concrete mix and for construction purpose. Recycled water is generally treated as reclaimed water means water recycled from various sources.
Introduction:
Due to rapid industrialization, urbanization, the effect of globalization all through the world increased the consumption of concrete in construction works. As such concrete playing a major role in development of infrastructure facilities. Concrete a mixture of cement, water, course aggregate, fine aggregates; increase in consumption of concrete increased the utilization of natural resources. Water a major component in making concrete mix as we say potable water or domestic water used for drinking purpose is suitable for concrete mix.
Scarcity in potable water is made to look for alternative sources of potable water. Only about 2% fresh water is available in the world of which nearly 96% is locked in the form of polar ice and snow. Water for concrete is used in two ways of, for mixing concrete and for curing purpose. Quality and quantity of water used in concrete will directly effects the properties of concrete like, setting times, strength, workability properties. The treated waste water or reclaimed water is an alternative source for water collected at the initial stage of treatment from various industries, domestic purposes, boilers etc, can be collected and is used for concrete mixing purpose.
Water for concrete purpose:
Potable water that is free from organic matter is used for concrete mixing. Actually water forms cement paste that is made by cementations materials by reaction process known as hydration. The cement paste that is ...
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...lution content and also compressive strength decreased nominally. As a result we can say that reuse of wastewater in concrete mixing can be made which is feasible in nature and potable water can be used for human needs.
Therefore there is a need to develop wastewater treatment plants in a economical way so that less amount of potable water is used for construction purpose and in result usage of potable water is prevented and application of reuse water can be increased. For use of reclaimed water a communication is required between the concrete industry people and communities which produce wastewater. There is a need to educate public in efficient usage of sustainable resources by recycling process and also about handling these treated materials as a result utilization of resources and also protection of health of human which are using reclaimed water can be made.
In 2004, plan was developed to increase the water supply through dams instead of water recycling. In 2006, focused were on the recycling water
In this paper report we have discussed about the use of recycled concrete aggregate in the concrete and the effects on its compressive strength by progressively replacing the natural concrete aggregate (NCA) by recycled aggregate. It is the experimental study of recycled concrete aggregate (RCA) when it is compared with the natural concrete aggregate on account of its properties.
Aitcin P.C, “Cements of yesterday and today Concrete of tomorrow”, Cement and Concrete Research, Vol. 30, (2000), pp 1349 - 1359.
Concrete today is considered by many modern engineers and architects as a more efficient and effective alternative to steel n regards to the creation of buildings, ranging from low-story apartments to neck-breaking skyscrapers. Through the rapid growth and development of the world's major metropolises and growing cities, concrete today has become one of the most important building materials to date. According to the World Business Counsel for Sustainable Development (WBCSD), “it has become the most consumed substance on earth, only superseded by water, with three tons for each person used annually” (World). This huge demand for concrete makes the cement industry one of the world's largest carbon dioxide producers, accounting for about five percent of all man-made pollution. “Approximately one ton of carbon dioxide is put into the atmosphere for every ton of cement used” (World). The cause for this problem is the increase of the global population and the increasing demand for land and energy. It's effect is that as the population continues to increase, it forces builders and developers to meet the quota of creating unlimited amounts of infrastructure within a limited resource-filled world. Knowing this, a proposed and widely agreed solution is to make the concrete in an environmentally-conscious way that will incorporate more demolished concrete, scrap from past projects, and other recycled aggregates.
Concrete is one of the world’s most popular construction materials. Some six billion tonnes of concrete is produced each year in the world, making it approximately one ton of concrete for every human being per year (Fardis, 2012, p.116). However, the lifecycle of concrete does not make it the most sustainable building material at the moment. Because of limited natural resources, concerns over green house gases, and landfill problems, concrete production is being cut-back, or at least cannot be increased to keep up with population increase. In this essay, I will look at what makes concrete an unsustainable material and possible solutions to make concrete a more sustainable material.
Concrete behaves as a back bone to nations building team. Concrete is a composite construction material composed primarily of aggregate, cement, and water. There are many formulations, which provide varied properties. But one of the disadvantages with the conventional concrete is high self weight of concrete. This heavy weight will make it some extent uneconomical structural material. Many attempts made in the past to reduce the self weight to increase the efficiency of concrete.
Turgut, P., & Yahlizade, E. S. (2009). Research into concrete blocks with waste glass. Int J Environ Sci Eng, 1(4), 202-208.
Concrete is a composite material used widely in the construction industry. Concrete is basically a mixture of cement, water, aggregates and admixture (sometimes). Cement is a fine gray powder that consists of oxidizes calcium, silicon and aluminum. The aggregate used is normally gravel, crushed stone or sand. Admixture is a solid or liquid substance that gives a certain characteristics of the concrete. The cement reacts with water chemically and binds the aggregates together through a process called hydration during hardening or curing of concrete. It means that water helps in the hardening of the concrete while the cement bind the aggregate and also react with water to form a solid mass.
There are numerous factors that determine the durability of a concrete. However, the main factor is the time needed to keep the concrete in a saturation state. Moreover, the reason a concrete normally undergoes early age shrinkage is that the concrete is being allowed to dry out too quickly. Figure 1 below shows an experimental result that is carried out to compare the strength of concrete by using different types of surfaces for 180 days. The surfaces are such as: -
In these cases, such as building a reservoir, a huge number of concrete trucks are generally brought in in a caravan, and they pour their concrete into the forms that have been constructed onsite. In some cases, this order will put a concrete plant out of commission for a period of time due to the demand, and as such it must obviously be coordinated ahead of time.
Basically a concrete structure must be capable of providing its intended use for a long period of time.To serve its purpose concrete must have high strength to carry the design loads in safe and efficient manner.The concrete through the structure must be of uniform quality because the structure is...
Workability depends on water content, aggregate (shape and size distribution), cement content and age (level of hydration) and can be modified by adding chemical admixtures, like super plasticizer. Raising the water content or adding chemical admixtures will increase concrete workability. Excessive water will lead to increase bleeding (surface water) and segregation of aggregates (when the cement and aggregates start to separate), with the resulting concrete having reduced quality. Workability of fresh concrete is determined by following
Author observed that overall performance of concrete was increased and there is huge reduction in water absorption [19]
Making concrete structure without compaction has been done in the past. Like placement of concrete underwater by the use of termie without compaction. Inaccessible areas were concreted using such techniques. The production of such mixes often used expensive admixtures and very large quantity of cement. But such concrete was generally of lower strength
Water undertake two important roles in concrete mixture. The first one is to act chemical reaction with cement and carry out cement hydration. Second one is to make the concrete become smooth and workable. Water used in concrete mixture should be clean and free of organic matter, any clear, drink and fresh water is acceptable. Impure water should be avoided in use and amount of water must be control carefully as they will lead to undesirable effect on concrete strength.