An interaction energy integral method for computation of mixed-mode stress intensity factors along non-planar crack fronts in three dimensions

A new interaction energy integral method for extracting mixed-mode stress intensity factors along the fronts of non-planar, three-dimensional cracks is described. In the method, interaction energy contour integrals are defined and expressed in domain form. The mixed-mode stress intensity factors are obtained by evaluating the domain integrals as a post-processing step in the finite element method. To assess the accuracy of the method, two benchmark problems are considered. The first problem is that of an arc crack in an infinitely extended solid subjected to equibiaxial tension. The second is that of a lens-shaped crack embedded in an infinite solid subjected to hydrostatic tension. Excellent agreement is obtained between the numerical and corresponding analytical results obtained from the literature.