T-SHAPED CRACK PROBLEM FOR BONDED ORTHOTROPIC LAYERS

The plane elasticity problem of two perfectly bonded orthotropic layer s containing cracks perpendicular to and along the interface is consid ered. Cracks are extended to intersect the boundaries and each other i n such a way that a crack configuration suitable to study the T-shaped crack problem is obtained. The problem is reduced to the solution of a system of singular integral equations with Cauchy type singularities . Numerical results for stress intensity factors and energy release ra tes are presented for various loading conditions and for isotropic as well as orthotropic material pairs. These results indicate that elemen tary strength of material type calculations for energy release rates p rovide a good approximation to the actual elasticity solution even for relatively short cracks, as long as the layer thicknesses are not ver y different.