Sustainability of High Performance Concrete: Use of Recycled Coarse Aggregate and Microsilica

Sustainable concrete production using RCA (Recycled Coarse Aggregate) and micro silica (pozzolanic material) provides a green solution to the continual depletion of NCA (Natural Coarse Aggregate). The study in this paper envisages the effective utilization of RCA obtained from old concrete for the production of High Performance Recycled Concrete. The paper highlights the fresh and hardened properties of HPRC using different proportions of micro silica. The paper outlines the comparison of compressive strength (CS), split tensile strength (STS), Flexural strength (FS) and workability of HPRC for different proportions of natural Coarse Aggregate (NCA) replacement with Recycled Coarse Aggregate (RCA) (0%,25%,50%,75% & 100%) and using different proportions of Micro silica dosage (5%,10% & 15%) Incorporating micro silica enhances the fresh and hardened properties of HPRC. Though the results of HPRC using higher proportions of RCA (beyond 50%)shows a sudden drop in both the fresh and hardened properties of HPRC but the results are still encouraging for the utilization of RCA using micro silica (10% dosage) for the production of HPRC.