Experimental investigation of the effects of aggregate and fiber percentage on the behavior and cracking potential of Engineered Cementitious Composites

The aim of this study is to determine the effect of replacing polyvinyl alcohol (PVA) fibers, fly ash (FA), and silica aggregate with polypropylene (PP) fibers, ground blast furnace slag (GBFS), iron furnace dust, limestone powder (LSP), natural sand, and microsilica to improve the mechanical properties and ductility of Engineered Cementitious Composites (ECC). Twelve different mixtures of ECC were designed and prepared. For each mixture, flexural and compression specimens were made and tested. The combination of microsilica and GBFS increases the strength and ductility of the composite, making it a viable alternative to fly ash. Replacement of silica sand with LSP that contains the appropriate composition can enhance ECC. The best results were achieved in ECC when the cementitious materials ratio was 1.25. By increasing the percentage of PP fibers from 1 to 1.5, the flexural strength increased by 65 percent, the middle span deflection of the flexural specimen increased by 21.7 percent, and the optimal amount of PP fibers to initiate hardening was 1.5 percent.