Implementation of a physics‐based general elastic imperfect interface model in the XFEM and LSM context

Abstract

SummaryWhen reinforcement particles of composites are imperfectly bonded to the matrix media, the interfacial effect may significantly change the physical fields and the material overall moduli. In this paper, we first recall a physics‐based general isotropic interface model of our companion paper to describe such effects. This model is characterized by both the displacement and normal traction discontinuities across an interface and includes the spring‐layer interface model and the coherent interface model as particular cases. The strong and weak governing formulations of composites with arbitrarily shaped imperfect interfaces are provided, and a computational approach is developed in the extended finite element method and level set method context to capture the interfacial discontinuities. To examine the performance and validity of the computational approach, the analytical solution of our previous work is used as a benchmark and several bulk and interface material combinations are considered. It is observed that the slowest convergence rate of our approach is no less than 1.45 for all investigated cases, and that both the predicted displacements and normal tractions are in excellent agreement with the analytic solutions. Finally, the influences of material compositions and periodic boundary conditions are evaluated numerically and discussed with a heterogeneous material containing multiple particles.