Elastic-Plastic Dynamic Fracture Analysis of Structural Elements Due to Stress Wave Propagation

초록

The present paper describes a dynamic fracture behavior of structural element under an elastic and elasto-plastic stress wave in two dimensional space. The governing equation of these problems is the type of hyperbolic partial differential equation, which consists of equations of motion and elastic constitutive equation in elastic problem or incremental elasto-plastic constitutive equations in elasto-plastic problem. To solve these problems we use the bicharacteristic method and Zwas' method based on the finite difference method. Additionally, in order to deal with the dynamic behavior of some elasto-plastic problems, an elasto-plastic loading path in the stress space is proposed to model the plastic yield phenomenon. We will show the characteristics of stress waves propagating in elastic medium and calculate the stress intensity factor obtained by numerical simulation using shadow optical caustic to compare the stress intensity factor with the experimentally obtained caustic performed by Kalthoff. The calculation using the method of bicharacteristic and Zwas method was carried out and their results were compared. The time history of a plastic zone of a elasto-plastic material was obtained by the Zwas method and its results are shown.