Utilization of various ceramic waste as fine aggregate replacement into fly ash-based geopolymer

This study aims to utilize a range of ceramic waste to replace sand as a fine aggregate in fly ash geopolymer. Ceramic waste aggregates comprised of brick (BR), floor tile (FT), roof tile (RT), and sanitary ware (ST) have been employed for river sand replacement at 0 %, 25 %, and 50 %. The development in compressive strength was investigated on geopolymer mortar at the ages of 7, 14, and 28 days. The results showed that incorporating FT, RT and ST aggregates exhibited comparable and even higher compressive strength than natural sand. The optimum compressive strength was achieved at 47.4 MPa for 50 % ST specimen, accounting for a 17.52 % improvement. The microstructure revealed that ST aggregates exhibited better interfacial transition zone (ITZ) than sand aggregate, thereby increasing the compressive strength of geopolymer mortar.