Acid resistance and durability properties of steel fiber-reinforced concrete incorporating rice husk ash and recycled aggregate

Recycled concrete aggregate (RCA) produced from concrete waste has recently been a good alternative to natural aggregate because of the increased focus on sustainable development and environmental benefits. However, concrete incorporating RCA has inferior properties when compared to natural aggregate concrete. The inferior properties of RCA concrete can be improved by incorporating supplementary cementitious materials (SCMs). Fly ash and silica fume are commonly used SCMs in the concrete industry which improve the mechanical properties and durability of concrete. Nevertheless, there is an imminent deficiency of material in certain parts of the world, and finding a replacement is a challenge for the future of the concrete industry. Rice husk ash (RHA) is a waste material that can be used as a partial replacement to improve the inferior property of RCA concrete. In this study, mechanical properties such as compressive strength and splitting tensile strength are studied. Durability properties such as water absorption, chloride diffusion and acid attack were also investigated. Furthermore, fibrous and non-fibrous concrete were made to study the effect of RHA and RCA. The results revealed that RHA can be used to mitigate the poor performance of RCA concrete and improve the bond between concrete and fibers. (C) 2019 Elsevier Ltd. All rights reserved.