Abstract:
Conventionally the concrete production is highly energy intensive and one of the main sources of greenhouse gas emissions in the World. The high strength concrete (HSC) is a trendy and effective solution for many structural applications. This concrete is particularly beneficial in compression members as it can endure higher stresses. In general the HSC requires the higher cement content and quality aggregates to achieve designated strength. However this process adds to the economy of the HSC production. Therefore replacement of supplementary cementitious materials and aggregates in HSC could lead to economical and sustainable manufacturing. Thus, the objective of this research is to investigate the effect of partial replacement of untreated rice husk ash (RHA) together with recycled coarse aggregate (RCA) on the engineering properties of HSC. Sixteen various mix propositions were examined by replacing the cement and natural coarse aggregates by RHA and RCA respectively to investigate the compressive and tensile strengths. Further the influences of untreated RHA and RCA on other engineering properties including air-entrainment, modulus of elasticity, workability were examined. Replacement of RCA up to 100 % did not significantly alter the strength properties of HSC. The addition of RHA up to 20% has reduce the compressive and tensile strength by only 10%.
