The effect of hybridization and geometry of polypropylene fibers on engineered cementitious composites reinforced by polyvinyl alcohol fibers

In the present study, the hybridization effect of polypropylene (PP) with polyvinyl alcohol (PVA) fibers in engineered cementitious composites (ECCs) was investigated. For this purpose, PVA reinforcing fiber was partially replaced by PP fibers with different circular, triangular, and trilobal cross-sectional shapes. The flexural behaviors of the ECCs containing hybrid fibers including first-crack strength, post-crack strength, and toughness were studied under three-point bending test. It was found that hybridization with nonround cross-sectional shape PP fibers had positive effect on the ductility but decreased the flexural strength of resultant ECCs. The greater reduction in toughness and post-peak strength was observed for composite containing circular PP fibers. The results indicated that partially replacement of PVA fibers with nonround cross-sectional shape PP fibers can be considered to be promising method to reduce the costs of ECC production along with attaining improved deformability.