Effect on Mechanical Properties of Concrete Using Recycled Coarse Aggregate Replacing Stone Chips

Abstract

Due to the scarcity of stone chips, construction works are obstructed day by day specially in developing countries. However, many infrastructures are broken because of they have reached at design period or other reasons. They have no salvage value but produced a huge dust on the environment. The aim of this works is to produce concrete with the recycled materials and to compare the mechanical properties with concrete made with stone chips. In sub-continent clay burnt bricks are available and aggregate produce from bricks are also available. For this reason brick aggregate has been used in the research work. Several physical properties were studied such as gradation, unit weight, specific gravity, and water absorption capacity of recycled aggregate. In addition, compressive strength, splitting tensile strength, flexural strength, modulus of elasticity, were determined as the mechanical properties of concrete made with recycled aggregate by replacing stone chips. Forty eight (48) cylinders of 4 in x 8 in and twelve (12) prisms of 18 in x 4 in x 4 in with an effective length of 13.5 in have been used. 10%, 20%, 30% and 100% recycled coarse aggregate have been used replacing stone chips for the research works. All tests have been carried out according to ASTM standard requirements. Water cement ratio was kept as 0.47 throughout the work. It has been seen that 10% percent replacement of recycled aggregate give optimum value of given mechanical properties which indicate recycled aggregate can widely used for construction.