A Study on Partial Replacement of Cement with Metakaolin and Fine Aggregate with Waste Foundry Sand

Abstract

Due to constant sand mining, the natural sand is depleting at an alarming rate. So, there is a need to find alternative to natural sand.The aim of the present study is to evaluate the effect of replacing cement with metakaolin and fine aggregate with waste foundry sand. For this study M25 grade concrete is prepared and is evaluated for fresh concrete properties and hardened concrete properties like compressive, split tensile, flexural strength and modulus of elasticity. Ordinary Portland cement is replaced with metakaolin keeping10% constant, while the fine aggregate is replaced with waste foundry sand at 0, 10, 20, 30 and 40% by weight. The compressive, split tensile and flexural strength properties are compared among all the mixes at periods of 7, 28 and 56 days. The results show that the use of metakaolin and waste foundry sand improves the mechanical properties of concrete. The optimum results were observed at 10% and 30% replacements of metakaolin and waste foundry sand respectively. The increase in compressive strength at 28 and 56 days was found to be 29% and 28.9%, which is 40.1MPa and 41MPa when compared to the nominal mix which is 31MPa and 31.8MPa respectively.