Mechanical and durability evaluation of fiber-reinforced self-compacting concrete

Abstract In this paper, an investigation of the mechanical properties and durability aspects of steel, synthetic, and hybrid fiber-reinforced self-compacting concrete exposed to early wet/dry cycles are presented and discussed. The experimental program consisted of two phases. Phase I involved tests on specimens for workability, mechanical properties, Rapid Chloride Penetration (RCP), and Scanning Electron Microscopy (SEM). The evaluation of mechanical properties included compressive, flexural and splitting tensile strengths, and modulus of elasticity. In Phase II, specimens were exposed to wet/dry cycles, and the effect of moisture on mechanical properties was investigated. All mixes in Phase I achieved a cube compressive strength of 70 ± 5 MPa. Furthermore, it was observed that exposure of Fiber-Reinforced Self-Compacting Concrete (FRSCC) to early wet/dry cycles improved the mechanical properties of all mixes; an increase in compressive strength of 10 MPa compared to non-exposed specimens was observed. The microstructure of Synthetic Fiber-Reinforced Self-Compacting Concrete (SyFRSCC) and Steel Fiber-Reinforced Self-Compacting Concrete (SFRSCC) was different, which explains the difference in their respective crack-resistance mechanisms.