Notch depth‐dependent flexural behavior of high‐performance fiber‐reinforced concrete under static and cyclic loading

Abstract This study aims to explore notch depth‐dependent flexural behavior of high‐performance fiber‐reinforced concrete (HPFRC) under static and cyclic flexural load. All specimens with their size of 40 × 40 × 160 mm (width × depth × full length) and span of 120 mm were tested under three‐point bending load. Three HPFRC types included: no fiber (HPFRC0), 1.0 vol% long hooked fiber blended with 0.5 vol% short smooth fiber (HPFRC1), and 0.5 vol% long hooked fiber blended with 1.0 vol% short smooth fiber (HPFRC2). Three notch depths of 5, 10, and 15 mm were studied for each HPFRC type. Under static load, there were clear reductions in load‐carrying capacity, deflection capacity, critical stress intensity factor, and critical energy release rate, but there was an increase in elastic modulus and crack mouth opening displacement as the notch depth increased from 5 to 15 mm, regardless of the HPFRC type. Generally, the order of the HPFRC type in terms of static flexural resistance was HPFRC0 < HPFRC2 < HPFRC1. Under fatigue load, at the high fatigue stress ratio of more than 0.6, the endurance limits of the HPFRCs reduced with increasing notch depth. Besides, the HPFRCs can be categorized as high‐cycle fatigue materials since their cycle number changed from 100 to 1,000,000.