Numerical study on the local damage of reinforced concrete column caused by a vertical impact load

Horizontal crack of reinforced concrete column caused by an earthquake was simulated by the hydrocode AUTODYN. This type of concrete crack was observed peculiar at the earthquake in Hyogo in 1995. Harada et al. hypothesized that this horizontal crack was produced by the vertical shock of this earthquake and verified this hypothesis by experiments. But the mechanism to initiate horizontal crack still contain uncertainty. In the present study, Harada's experiment was simulated by the hydrocode and the mechanism to initiate the horizontal crack was investigated. In the numerical simulation, our developed constitutive equation of concrete with strain hardening and strain rate dependency was applied. Fracture behavior was evaluated by the failure criterion for the tensile strain. The results let us know the detail of the stress state of the concrete column which initiate crack and the final damaged region inside the concrete pillar. We can conclude that the dynamic nonlinear behavior of concrete column on a vertical impact loading was simulated quantitatively by our method and the mechanism to introduce horizontal crack was theoretically studied.