Performance of Reinforced Concrete Beam with Rubber as Partial Replacement for Coarse Aggregate

Abstract

Concrete which is made from cement, coarse and fine aggregates and water is the most used material in the world after water. All aggregates used in concrete are naturally obtained material. So a substitute must be found to replace natural aggregate to avoid the exhaustion of natural resources. On the other hand in India the volume of tyre rubber wastes is increasing. An estimated 1000 million tyres reach the end of their useful lives every year and 5000 million more are expected to be discarded in a regular basis by the year 2030 (Sofi, 2018). The growing problem of waste tyre disposal in the India can be alleviated if new recycling routes can be found for the surplus tyres. One of the largest potential routes is using the waste tyre rubber in construction. This study investigates the potential of incorporating recycled rubber tyre chips into Ordinary Portland Cement (OPC) concrete. This research evaluates the behaviour of reinforced concrete beam made with chipped rubber concrete as partial replacement for coarse aggregate. The research work was divided into three phases. In phase I, the mechanical properties such as workability, compressive strength and tensile strength of concrete with 0%, 5%, 10% and 15% chipped rubber aggregate as partial replacement for coarse aggregate were determined. Compressive strength was found out using 150 mm concrete cube and tensile strength was determined using concrete cylinder of diameter 150mm and height 300 mm. It is observed that rise in percentage of substitution of chipped rubber beyond 10% reduce the compressive strength. Hence investigation on flexural behaviour of RC beam was conducted with 5% and 10% replacement of coarse aggregate with chipped rubber. The crack pattern, load- deflection behaviour, moment-curvature and ductility of RC beam were studied.Durability study on rubber aggregate concrete was also done by immersing concrete cube in 5% H2SO4 solution as per ASTM C-267. Total of 233 specimens were tested under phase I study.