非线性断裂动力学中的路径无关积分和断裂准则

本文考虑非线性断裂动力学中的路径无关积分和断裂准则.在讨论中计入了动力效应和裂纹的传播现象,考虑了裂纹在非线性弹性介质中的传播以及在弹塑性介质中的传播二种情况,作出了一些相应的路径无关积分.作为例子.讨论了裂纹的定常传播情况.最后,给出了这种路径无关积分的力学意义.说明它可用来作为非线性断裂动力学的一种断裂准则.

On Path-Independent Integrals and Fracture Criteria in Nonlinear Fracture Dynamics

In this paper, we consider path-independent integrals and fracture criteria in nonlinear fracture dynamics. The dynamic effect and crack propagation are included in the discussion. Both nonlinear elastic and elastic-plastic case for crack propagation have been considered, and the related path-independent integrals are proposed. As an example, the steady state propagation of crack has been discussed. Lastly, we give the mechanical meaning of this path-independent integrals as the crack extension force, and make it possible to use the path-independent integrals as fracture criterion in nonlinear fracture dynamics.