A Novel Approach for Evaluation of Stress Intensity Factors Using X-FEM

A new energy approach is proposed by coupling the virtual crack extension with the extended finite element method (X-FEM) to extract the Strain Energy Release Rates and then convert it to stress intensity factors. By means of meshes independence of the location and geometry of the crack, the proposed approach avoids the mesh perturbation around the crack tip to compute the stiffness derivatives with respect to a virtual extension of the crack. In comparison to the interaction integral, this combined method is implemented more easily without the post-processing of the numerical results. The effect of different enriched region around the crack tip on the accuracy of results is discussed. Numerical results presented are in excellent agreement with the available analytical and those obtained using the interaction integral.