Azam Tabatabaei - Graduate Student, Department of Civil Engineering, Yazd University
Amir M. Halabian - Assistant Professor, Department of Civil Engineering, Isfahan University of Technology
Kazem Barkhordari - Assistant Professor, Department of Civil Engineering, Yazd University
S. Hamid Hashemolhosseini - Associate Professor, Department of Mining Engineering, Isfahan University of Technology

The response of some soil-structure systems such as lined tunnels, retaining walls and etc. can be affected by the soil-structure interface behavior. Interacting forces induced at the soil-structure interface is influenced by the existence of interfaces defined as thin layers of soil in which stresses are transferred from one medium to another. Therefore, the numerical simulation of soil-structure interaction problem requires proper modelling of the interface. Using the similarity between the soil behavior and interface deformations the classical soil plasticity is employed to develop an interface constitutive to include deviatoric hardening/softening, compaction and dilatancy and ultimate states. The predictions of the model are first presented and then compared with available experimental data from various interface tests. The model was successfully used to predict the behaviour of some interfaces with different soil parameters.

Soil-structure interface, Elasto-plasticity, Constitutive model, Critical state soil mechanics