ASYMPTOTIC AND NUMERICAL-ANALYSIS OF A CRACK BRANCHING IN NONISOTROPIC MATERIALS

The analysis of 2D crack propagation, in a homogeneous elastic but non-isotropic material, is performed by comparing the initial state of a structure with a preexisting crack to its final state including in addition a small straight kink emanating from the original crack tip. Asymptotic expansions are provided for the final solution as well as for the stress intensity factors, the change in potential energy and the energy release rate. A numerical application of a revisited Griffith criterion is suggested, involving anisotropic fracture properties. Stability of the kink is derived.