The paper presents an effective analytical method for soil-structure interaction systems, which can have separation or sliding. The method is based on the coupling of infinite-finite element to carry out time-history analysis on tunnel. In the same time, material plasticity of concrete is also induced in this method. Perfect bound model, classic Coulomb friction model and Goodman element are used. The distribution of max principal stress, plastic hinge and the degree of the separation and slipping between soil and structure are analysized.