STUDY ON THE COUPLING MODEL OF CRACK WITHOUT REMESHING BASED ON X-SBFEM

The extended finite element method (XFEM) without remeshing has to adopt complex interpolation function based on analytic solution in the crack tip. Besides, the computational accuracy is affected by mesh density and interpolation function. The scale boundary finite element method (SBFEM) has great advantage in solving problems characterized by stress singularity and infinite domain. Because both methods are combined into the finite element theory, a fracture numerical coupling model with the advantages of the two methods can be established. Based on the principle of virtual work, a new fracture numerical method called X-SBFEM is proposed by taking advantage of the displacement coordination and the force balance mechanism. In this method, the crack body is simulated by XFEM and the crack tip is simulated by SBFEM. During the numerical evaluation, this algorithm is validated by calculating the stress intensity factors of cracks, which is compared with the theoretical solution.