Numerical evaluation of 3-D SIF for arbitrary finite element meshes

Abstract

An innovative procedure, based on the domain integral method (including the effects of body forces, crack surface tractions, temperatures and pore pressures) to determine stress intensity factors along a crack front in arbitrary three-dimensional (3-D) finite element mesh, is presented. The domain integral is evaluated over a tubular domain defined independently of the mesh layout. A Gauss integration scheme, in cylindrical coordinates, is devised to facilitate numerical integration. An important characteristic of the proposed implementation is that it does not require a special layout of finite elements around the crack front and, thus, can easily be used in conjunction with 3-D mesh generators. The new implementation is validated on 3-D problems and is shown to provide an acceptable engineering accuracy.