Development of strain-hardening cementitious composites utilizing slag and calcium carbonate powder

Strain-Hardening Cementitious Composites (SHCCs), utilizing slag to replace fly ash and a calcium carbonate powder to replace silica sand, were developed in this study. The underlying motivations were to reduce the variation in SHCC's mechanical properties caused by the inherent variation in fly ash properties and to investigate the influence of using calcium carbonate powder along with slag on these properties. A response surface design of experiments was used to systematically investigate the effects of the two ingredients – slag and calcium carbonate powder – on the mechanical properties of SHCC and determine the optimum mixture composition. These two ingredients showed significant independent effects as well as interaction effects on the properties of SHCC. The best-performing SHCCs developed in this study exhibited mechanical properties similar to conventional SHCCs but with reduced variability in mechanical properties and improved material sustainability.