Notch Depth-Dependent Cyclic Fracture Energy of High-Performance Hybrid Steel Fiber-Reinforced Concrete Under Bending
摘要
An experimental study was conducted to assess the notch depth-dependent cyclic fracture energy of high-performance hybrid steel fiber-reinforced concrete (HP-HFRC) under bending. The HP-HFRC was reinforced with 1.5% hybrid steel fiber by volume (0.5% long hooked fiber combined with 1.0% short smooth fiber). All specimens having their depth × width × length of 40 × 40 × 160 mm3 were subjected to cyclic three-point bending load. Four depth notches designed at the middle span were investigated as follows: 0 mm (N00), 5 mm (N5), 10 mm (N10), and 15 mm (N15). The fracture energies of the HP-HFRC were derived for the first 20 cycles under two fatigue stress ratios of 0.4 and 0.5 times of the static modulus of rupture. The results were that the N05 series exhibited the highest elastic fracture energy, plastic fracture energy, and total cyclic fracture energy. Besides, the elastic fracture energy was clearly higher than the plastic fracture energy, regardless of notch depth value.