Determination of Stress Intensity Factors for Interfacial Cracks Using the Virtual Crack Extension Approach

Abstract: A new finite element analysis procedure is implemented for the determination of complex stress in-tensity factors in interfacial cracks. Only nodal displace-ments and strain energies of the near-crack-tip elements are involved in this procedure so that element stiffness matrices need not be made available. The method is first tested using a closed form solution for infinite media to obtain a suitable finite element mesh. It is then applied to finite plates and four-point bending specimens contain ing interfacial cracks. In cases where reference values are available for comparison, good agreement of results can be obtained with relatively coarse element meshes