Mohsen Kamalian - Professor, International Institute of Earthquake Engineering and Seismology, Tehran, Iran
Masoud Amel Sakhi - Assistant Professor, Department of Civil Engineering, Qom University of Technology, Qom, Iran
Behrouz Ahmadpour - Master Student of Civil (Geotechnical) Engineering, Qom University of Technology, Qom, Iran
Mostafa Tavakoli - Master Student of Civil (Geotechnical) Engineering, Qom University of Technology, Qom, Iran

In plastic models like Mohr-Coulomb (perfect plastic) yield surface is constant in stresses space. In contrast to these models, in hardening models, yield surface expands due to plastic straining. Hardening Soil model (HS) shows realistic and exactly assessment of soil actual behavior, so it should be considered in projects. In this paper sheet pile excavation is defined and Mohr-Coulomb and Hardening Soil models using finite element method are considered, separately. The located soil in back of the wall is modeled in different layered models. Obtained results show increase 7, 23, 45 and 30 percent in the axial force, shear force, bending moment and horizontal displacement of sheet piles on the completion phase of excavation in Hardening Soil model, respectively. Also axial force of struts are increased. Results show that layering of soil in back of excavation support system has no effect on obtained results.

Constitutive Model, Mohr-Coulomb model, Hardening Soil, Sheet piles supporting system