Elastic effect in dynamic response of beams with pre-cracks impinged by striker

To examine the effect of elasticity on dynamic response of imperfect structures, by densely setting meshes in the vicinity of the imperfections, pre-cracked beams impinged by a striker are modeled and numerically investigated. The dynamic response patterns and failure history for two specific configurations are obtained. It is found that complex alternations of the elastic-plastic stress distribution exhibit, and the striker is rebounded and then separated from the beam, which well reflects the effect of material elasticity. The high stress and large deformation zones, corresponding to the plastic hinges in the rigid-plastic model, appear at the impinging position and the supporting ends, and the locations coincide with those in the modal pattern in rigid-plastic response. It is concluded from comparison that when the impinging is intense, despite the effect of elasticity displaying in the early stage, the widely employed rigid-plastic analysis is still capable of providing favorable prediction on the final response parameters.