Improvement of Elastic-Plastic Fatigue Crack Growth Evaluation Method : 3rd Report, Study on Effective J-integral Range Estimation Method

Evaluation of crack growth behavior under cyclic loading is often required in the structural integrity assessment of cracked components. The effective J-integral range is widely used in characterizing crack growth under cyclic loading with large plastic deformation. However, methods for estimating it for cracks in actual components are not well established because of several difficulties. In this study, a formulation for evaluating the effective J-integral range by the finite element analysis was presented and applied to center cracked plate specimens. Then a simplified estimation method using the reference stress and the crack opening ratio was proposed and its effectiveness was demonstrated through a comparison with the results of finite element analysis.