Fiber fraction-dependent flexural behavior of high-performance fiber-reinforced concrete under static and repeated loading

The effect of the fiber volume fraction on the flexural behavior of high-performance fiber-reinforced concrete (HPFRC) under both static and repeated loading is highlighted through a series of experiments. All rectangular prism-shaped flexural specimens were 40 × 40 × 160 mm3 and subjected to a three-point bending (3 PB) fixture with a span length of 120 mm. Macro-hooked and micro-smooth steel fibers with volume contents of 0.0%, 0.5%, 1.0%, and 1.5% were investigated. The flexural strength and deflection capacity of the HPFRCs under static loading generally increased with increasing fiber volume content. The micro-smooth fiber mostly produced a higher flexural strength and a lower deflection capacity compared to the macro-hooked fiber. Under repeated loading, a larger fiber volume fraction generally resulted in higher HPFRC endurance limits, which exceeded 40,000 cycles with a fatigue stress ratio of