Weight function approach to a crack propagating along a bimaterial interface under arbitrary loading in an anisotropic solid

The focus of this paper is the study of the dynamic steady-state propagation of interfacial cracks in anisotropic bimaterials under general, nonsymmetric loading conditions. Symmetric and skew-symmetric weight functions, defined as singular nontrivial solutions of a homogeneous traction-free crack problem, have been recently derived for a quasistatic semiinfinite crack at the interface between two dissimilar anisotropic materials. In this paper, the expressions for the weight functions are generalized to the case of a dynamic steady-state crack between two anisotropic media. A functional matrix equation, through which it is possible to evaluate the stress intensity factors and the energy release rate at the crack tip, is obtained. A general method for calculating the asymptotic coefficients of the displacement and traction fields, without any restrictions regarding the loading applied on the crack faces, is developed. The proposed approach is applied for the computing stress intensity factors and higher-order asymptotic terms corresponding to two different example loading configurations acting on the crack faces in an orthotropic bimaterial.