Valiasr junction is a heavy urban area in the middle of Tehran. Several bus and metro stations are located around it. After construction of underpassing, pedestrians can access the north, sought, east and west of the junction without any traffic problem on the surface. On the other hand, a metro line is located in the depth of 9 m from the surface. Furthermore, intersections are planned in the underpassing. Simulation of construction of the tunnel intersections with soil overburden of about 3m is the main goal in this paper. Main section is simulated by 2D soil-structure interaction analysis using finite element method (FEM). Furthermore, combination of 2D soil-structure interaction analysis and 3D FEM analysis are used for modeling of intersections. The results are achieved through the comparison of deformations (surface settlement and crown displacements) and mobilized forces in the lining elements. The results revealed the efficiency of the sequential tunneling method (SEM) accompanied by forepoling technique for safe construction of underpassing with low soil overburden. Therefore, combination of forepoling and NATM tunneling stages was chosen as the design method for construction of the Valiasr underpassing.
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