Utilization of the Capacity for Energy Absorption of Concrete Structures under Impact

Concrete structures subjected to impact have shown a higher sensitivity to develop a brittle shear failure than under quasi-static loading. The differences between the dynamic and static behavior are due to the strain-rate dependence of material properties and the presence of inertial forces. Both effects should be accounted for when performing analyses of structures under impact. In the present paper, a simplified three-degree-of-freedom model is used to understand the improved impact response of reinforced concrete when steel fibers are added to the concrete matrix. The analysis shows that the higher capacity for energy absorption of fiber-reinforced concrete (FRC) may avoid local shear failure when the FRC is able to develop strain hardening prior to the peak strength. Various analyses are presented in order to understand the influence of different types and contents of fibers.