Compressive Strength of Concrete f’c = 210 kg/cm² with Coarse Aggregate Substitution at 20%, 25%, and 30% Using Recycled Concrete

Abstract

The present research project evaluates the compressive strength of concrete f’c = 210 kg/cm², using recycled concrete coarse aggregate (RCCA) sourced from demolition waste at substitution rates of 20%, 25%, and 30%. The physical-mechanical properties of both RCCA and natural aggregate were determined, followed by mix design using the ACI method. The experimental design included a control group (base concrete) and three experimental groups tested at 7, 14, 21, and 28 days. A total of 96 cylindrical specimens were analyzed. Results showed that RCCA concrete surpassed the design strength f’c = 210 kg/cm², achieving an average compressive strength of f’cr = 340.58 kg/cm² at 28 days, with increases of 9.48%, 17.81%, 15.29%, and 16.63% compared to the base concrete. These findings demonstrate that RCCA is viable for structural applications in construction.