Enhancing the mechanical and durability properties of bio self-compacting sand concrete containing granite industrial waste as a fine aggregate: an experimental study

Self-compacting sand concrete (SCSC) is a highly fluid concrete widely used as a building material. The present investigation examined the impact of using seashell powder (SSP) and granite waste (GW) as supplementary cementitious material and fine aggregate, respectively, on the mechanical properties and elevated temperature durability of SCSC. For this purpose, SSP and GW were used to substitute 5, 10, and 15% by weight of cement and 10, 20, 30, and 40% by volume of natural sand, respectively. The fresh and hardened properties of SCSC mixtures were studied through a variety of tests, including setting time, slump flow, compressive strength, flexural strength, compactness, abrasion resistance, and elevated temperature resistance. SEM analysis was also carried out to investigate the developing microstructural properties of hardened SCSC mixtures. The results indicated acceptable fresh properties with low superplasticiser dosages in SCSC mixtures for up to 40% GW replacement. The compressive and flexural strengths improved by 30.61% and 35.82%, respectively, after 90 days of curing for SCSC mixtures with 10% SSP and 40% GW compared with the control mixture. Moreover, the incorporation of SSP in SCSC mixtures with varying levels of GW resulted in the best durability, while 40% GW improved their abrasion and elevated temperature resistance. The study demonstrates that the combined use of SSP and GW in the production of green self-compacting sand concrete is feasible in terms of both mechanical and durability properties.