Analysis of Z-branch from a pre-existing slipping crack in an anisotropic solid

The problem of Z-branch from a pre-existing slipping crack in an anisotropic solid is formulated in terms of a system of singular integral equations, which is developed by way of Stroh formalism. The frictional forces existing on the slipping crack are directly incorporated into the formulation. A numerical method is then employed to solve these equations. Two points are addressed in the present investigation. First, the problem of an infinitesimally small branched crack length is investigated, in which the effects of frictional forces on the stress intensity factors at the branched crack tips are studied. Then the level curves for the stress intensity factors and energy release rate are given, which are plotted versus various branch lengths and branch angles for the case of frictionless slipping surface problem. From the level curves some phenomena are observed and results are discussed.