ENERGY RELEASE IN FRACTURE OF RATE-DEPENDENT MATERIALS

摘要

A general, steady-state crack propagation problem is considered for both periodically structured and homogeneous media with rate-dependent moduli and/or density. The influence of the surface structure described by a specific dynamic condition at the crack faces is examined as well, and the energy release associated with the surface structure is determined. A general, structure- and crack-speed-dependent expression of the wave resistance is presented. The conditions for the existence of energy release in a 'refined' model of the medium are shown and a procedure for the proper homogenization of a structured material (to be adequate for fracture dynamics) is found.