Dynamic Properties and Damage Model of Ultra-High Performance Fiber Reinforced Cement Composites Subjected to Repeated Impacts

摘要

Ultra-high performance fiber reinforced cement composites (UHPFRCC) is a new type of concrete with very high strength, ductility and durability and is expected to be used for innovative construction structures. The dynamic properties of UHPFRCC subjected to repeated impacts were investigated using the split Hopkin-son pressure bar. The dynamic damage to the UHPFRCC was measured by ultrasonic wave velocity methods after each impact. The influence of different fibers and the number of impacts was researched on the stress-strain curves and dynamic damage of UHPFRCC. A damage model was proposed to simulate the stress-strain curves of UHPFRCC subjected to repeated impacts. Results showed that the simulation values were very close to those of the experiments.