Finite element calculation of stress intensity factors for interfacial crack using virtual crack closure integral (Q1904917)

Using the virtual closure integral approach, the authors have developed a numerical method which significantly simplifies the computation of the stress intensity factors for an interfacial crack. This method computes the stress intensity factors for an interfacial crack from the crack opening displacements and the nodal forces ahead of the crack tip using a finite element model. Simple formulae which relate the stress intensity factors to the energy release rates are given for three separate categories: an isotropic bimaterial continuum, an orthotropic bimaterial, and an anisotropic bimaterial continuum. Accuracy and efficiency of the proposed numerical method is demonstrated by comparing the numerical solutions with the exact solution available for certain problems. Some additional studies have been carried out to examine the effects of the characteristic length on the stress intensity factors as well as on the fracture criterion based on these stress intensity factors.