Utilization of novel stranded steel fiber to enhance fiber-matrix interface of cementitious composites

Reinforced materials with helically twisted geometries have been successfully applied in the concrete structures, owing to their superior mechanical properties and anchoring capabilities. Helically twisted types materials with diameters less than 1.0 mm might be an ideal type of fiber for cement-based materials reinforcing. In this article, a novel stranded steel (SS) fiber was first proposed and realized by simply cutting the commercial steel strands. The fiber-matrix interfacial properties and mechanical performance of steel fiber reinforced cementitious composites (SFRCC) were investigated. It was found that the SS fiber-cement matrix interface demonstrated superior interfacial bonding performance, as compared to those for the interface between hooked-end/straight fibers and cement matrix. For the mechanical properties of SFRCC, cementitious composites reinforced by SS fiber exhibited strikingly outstanding mechanical property as any other types of steel fiber with the same fiber amount. In conclusion, SS fiber may be more suitable for cementitious composite reinforcement than hooked-end and straight fibers.