CHAPTER 2
LITERATURE REVIEW
2.1 CONCRETE
Concrete is a composite material composed of coarse granular material (the aggregate or filler) embedded in a hard matrix of material (the cement or binder) that fills the space among the aggregate particles and glues them together.
Concrete is widely used for making architectural structures, foundations, brick/block walls, pavements, bridges/overpasses, highways, runways, parking structures, dams, pools/reservoirs, pipes, footings for gates, fences and poles and even boats.
2.1.1 Composition of Concrete
Concrete consists of three major components, viz. water, Portland cement, and aggregates. Properties of the final product i.e. cement changes according to the change in the ratio of its components
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It mainly involves grading, crushing and washing with natural aggregates which in turn removes contaminant materials such as reinforcing steel, gypsum board, remnants of formwork and other foreign materials. The resulting coarse aggregate is then useful for use in concrete. The fine aggregate, however, generally contains a considerable amount of old cement paste and mortar which will increase the drying shrinkage and creep properties of the new concrete. After removing of contaminants through proper demolition, screening, and/or separation and size reduction in a crusher to aggregate sizes, crushed concrete can be used as new concrete for pavements, shoulders, median barriers, sidewalks, curbs and gutters, and bridge foundations, structural grade concrete and soil-cement pavement bases …show more content…
Based on the experimental observation, the sensitivity of granulated slag content, polypropylene (PP) fiber and steel fiber dosage fiber dosage on the residual compressive strength of the concrete after being subjected to elevated temperature was examined. Equations are proposed to predict the residual compressive strength of concrete incorporating with granulated slag, PP fiber and Steel fiber by giving it a high temperature up to 800°C. Test indicates that the exposure of concrete to a high temperature causes deterioration in the compressive strength of concrete but the inclusion of granulated slag, PP fiber and steel fiber, they all improves the residual compressive properties of concrete to some
Most people may not realise but concrete plays a vital part in our lives daily. It shapes and creates the built environment in which we are surrounded by, such as schools, bridges, roads, housing, hospitals, dams and so much mores. Concrete is the most used man made material in the world, averaging around 3 tonnes annually for each person. In comparison with other building materials such as wood, steel, plastic and aluminium, over twice as much concrete is used globally than any of these materials. It is the material choice of most purposes due to its strength, durability, thermal mass and its cost.
Almost no other material manages to carry such contradictory associations. Stigmatized on one hand, celebrated on the other, it evokes highly diverse reactions this material is cement. Cement is a finely ground powder binder, a substance that sets and hardens and can bind other materials together, when mixed with water forms a hardening paste of calcium silicate hydrates and calcium aluminates hydrates. Cement is used in mortar and concrete (bulk rock-like building material made from aggregate, sand, and water). By modifying the raw material mix and the temperatures utilized in manufacturing, compositional variations can be achieved to produce cements with different properties. Cement, chemically speaking, is a product including lime as the
In this paper we have studied compressive strength of concrete by replacing natural aggregate with recycled aggregate by 25%, 50% and 75%.This mixture formed in the sample of cubes of dimension 150x150x150mm3.
Khadiranaikar R.B. and Muranal S.M. (2012) “Factors affecting the strength of Reactive powder Concrete(RPC)” International Journal f Civil Engineering and technology volume 3 issue 2
2) While many High Performance Concretes exhibits rapid stiffening and early strength gain, other’s may have long set times and low early strengths.
[20] BS Part 116: 1983. Testing Concrete and determination of compressive strength. British Standards Institution ;
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.
Aggregate: in cement concrete to gain good quality aggregates are used in two groups. Sand and coarse
Reinforced concrete is stronger than basic concrete. Steel reinforcing bars known as rebar is incorporated in the concrete structure to act together in resisting the force. The steel reinforcing bars absorbs tensile and compression because plain conc...
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.
Generally the strength of concrete is represented by the crushing stress of concrete cube of size ………………………………..
The concrete industries progress showed that the concrete Slab-on-Grade can be modified to be stiffer and have a higher tensile strength. It may resist the changes in soil due to swelling for example.
The ratio of flexural strength to compressive strength of lightweight foamed concrete (LWFC) was in the range of 0.06-0.10 and this ratio was also found to reduce with increasing water-cement ratios and decreasing densities (Deijk, 1991). The splitting tensile strengths of LFC mixes were higher for mixes with sand than those with fly ash. This was attributed to the improved shear capacity between sand particles and the paste phase. (Jones and McCarthy, 2005)
Author observed that overall performance of concrete was increased and there is huge reduction in water absorption [19]
This study will focus on the chloride penetration to the concrete in various type of the strength and days of the concrete. This study is examined the effect of chloride to the concrete strength and durability of concrete on various type of concrete mixture proportion. Different type of concrete proportions mixture will give the dissimilar result of the experiment.