Stress intensity factor analysis by combination of boundary element and finite element methods. Application to mixed-mode crack problems.

Abstract

A combination of the boundary element method and the finite element method is used to calculate the stress intensity factors of mixed-mode crack problems. In this method, finite elements are only allocated near a crack tip and boundary elements are used to discretize the rest of the structure. The virtual crack extension method is applied to the finite elements to obtain the stress intensity factor, together with the method for the separation of displacement components into Mode I and Mode II. The analyses are performed for a center slant crack or a center arc crack in a rectangular plate subjected to uniform tensile stress. It is found from the analyses that the present method gives an accurate stress intensity factor for mixed mode crack problems.