Fracture Mechanics Analysis of Embedded Cracks in Plates

In this paper,the fracture behavior of plates with embedded off-set elliptical cracks under combined tension and bending is analyzed using 3-D elastic-plastic finite element（FE） method.The J-integral values obtained from the FE analyses for the crack tip at the smallest ligament are then compared with those estimated using the reference stress method.The results show that the reference stress method may underestimate the FE J when the global limit load is used.The reason could be that the plastic zone correction in the reference stress method is not sufficient to cover the plastic zone in the small ligament due to the ligament yielding.