Experimental studies on utilization of recycled coarse and fine aggregates in high performance concrete mixes

Abstract

This experimental study deals with utilization of Coarse Recycled Concrete Aggregate (CRCA) and Fine Recycled Concrete Aggregate (FRCA) in High Performance Concrete (HPC) mixes. The concrete mix is designed for target strength of 60MPa. Four mixes are considered in the study viz., Control Mix (CM) with natural aggregates, 20% replacement of CRCA, FRCA and both. The fresh and hardened properties are assessed for all the four mixes. The experimental results indicate the satisfactory performance of all the four mixes with respect to hardened properties. The HPC mixes with 20% FRCA content shows reduction in workability and requires a higher dosage of Superplasticizer (SP) to achieve a slump of 170±10mm. The durability tests such as sulphate and acid attack are conducted for the mix containing 20% CRCA and FRCA. The mix is found to be least susceptible to sulphate attack. The significant reduction in compressive strength is noticed, when the HPC mix is exposed to H2SO4 solution.