EVALUATION OF ENERGY-RELEASE RATE IN THE CRACK MICROCRACK INTERACTION PROBLEM

The crack-microcrack array interaction problem, in terms of the statistical distribution of microcrack length, density and orientation, is formulated in this paper. The formulation is based on Green's function of a dislocation dipole placed in the vicinity of the main crack tip. The energy release rate (ERR) associated with the microcrack array evolution is also formulated in terms of the distribution and their gradients. The effect of the microcrack density, length and orientation on stress intensity factors and ERRs are illustrated on examples.