Evaluation of blending elements in xfem on crack analysis and proposal for improvement of analytical accuracy

In the XFEM, elements with some of their nodes enriched are usually called 'blending elements (BE)'. Decrement in accuracy of the analytic solution in BE is associated to a lack of partition-of-unity. In this paper, the influence of BE on the analytical accuracy of fracture mechanics parameters based on J-integral method is first evaluated. Then, a newly proposed modeling methodology on the domain of enrichment, considering the J-integral path, is presented. This methodology is straightforward allowing avoidance of the direct influence of BE on the analytical accuracy. Therefore, analyses with sufficient accuracy in the minimum enrichment domain are effectively achieved by using the proposed methodology.