Utilizing waste materials in concrete: A review on mechanical and sustainable performance

The construction industry consumes more natural resources than any other sector, necessitating sustainability practices. Utilizing waste materials in concrete addresses disposal challenges while enhancing sustainability. Many waste materials possess pozzolanic properties, improving concrete performance. This review aims to examine sustainable concrete incorporating waste materials such as fly ash (FA), silica fume (SF), recycled concrete aggregate (RCA), slag (S), waste perlite powder (WPP), groundnut husk ash (GHA), and nano silica (NS). The methodology involves a comprehensive analysis of life cycle assessment (LCA) studies, country-specific waste production, and concrete performance focusing on environmental and economic impacts. Results show that FA, SF, S, WPP, and NS enhance concrete's compressive strength, with SF yielding a 41% increase at a 12% substitution rate. Additionally, substituting FA can reduce carbon dioxide (CO2) emission by 68% and combining 5% SF and 15% FA lower CO2 emission by 16% compared to reference concrete. Furthermore, combining WPP and RCA results in a 17% cost reduction compared to reference concrete, while GHA substitution decreases cost by up to 30%. These findings highlight the potential of utilizing waste materials to improve mechanical performance, reduce environmental impact, and lower construction costs. The review suggests future research directions to further improve performance.