Shear locking avoidance in the analysis of cracked plates by XFEM

A basic method to model cracks in plates is presented by using the extended finite element method (XFEM). This method is based on the traditional finite element method, and can conveniently reflect the existence of the cracks by means of increasing discontinuous function and asymptotic displacement function in the standard displacement field. Thus, the crack geometries are independent of the finite element model and this method can greatly facilitate the simulation of crack growth. The mixed interpolation (MITC4) used for solving the problem of Reissner plates is adopted, which can effectively avoid the phenomenon of shear locking. The mixed-mode stress intensity factors are derived by using the interaction integral. Finally, numerical examples are used to illustrate the feasibility and accuracy of this method.