Potential of bagasse ash as alternative cementitious material in recycled aggregate concrete

Abstract

The experimental study deals with assessing the potential of bagasse ash (SBA) as alternative for cement in recycled aggregate concrete. The natural coarse aggregate in concrete is partially replaced with 20%, 30% and 40% of the recycled coarse aggregates (RCA) and the cement is partially replaced with 10%, 15% and 20% SBA. The fresh properties of recycled aggregate concrete are assessed by conducting slump test. The slump increases with increase in the percentage of replacement of SBA and reaches 115mm in recycled aggregate concrete as compared to without SBA in recycled aggregate concrete. The hardened properties like compressive strength were assessed at 7 & 28 days, split tensile, flexural strength and modulus of elasticity were carried out at 28 days respectively. Compressive, split tensile strength, flexural strength and modulus of elasticity of recycled aggregate concrete decreased with increase in the percentage of replacement of RCA but with the partial replacement of cement with 10% SBA compressive, split tensile strength, flexural strength and modulus of elasticity of recycled aggregate concrete strength increases. The microstructural analysis revealed that interfacial transition zone of recycled aggregate concrete containing 10% SBA is better than recycled aggregate concrete without SBA. Based on test results, it can be inferred that 30% replacement of the RCA with NCA and cement with 10%SBA can be considered as optimum replacement level, considering its fresh, hardened and micro structural properties.