Dynamic fracture mechanics analysis for composite materials with material nonhomogeneity along thickness direction

The problem considered here is the response of non homogeneous composite material containing some cracks subjected to dynamic loading. It is assumed that the composite material is orthotropic and all the material properties only depend on the coordinates y(along the thickness direction). In the analysis, the elastic region is divided into a number of plies of infinite length. The material properties are taken to be constants for each ply. By utilizing the Laplace transform and Fourier transform technique, the general solutions for plies are derived. The singular integral equations of the entire elastic region are obtained and solved by virtual displacement principle. Attention is focused on the time dependent full field solutions of stress intensity factor and strain energy release rate. As a numerical illustration, the dynamic stress intensity factor of a substrate/functionally graded film structure with two cracks under suddenly applied forces on cracks face are presented for various material non homogeneity parameters.