Seismic Response Analysis of Station-Tunnel Transition Section Structure

To study the seismic response of station-tunnel transition section structure and provide reference for its seismic design, according to the practical engineering background of Tianjin metro line1, the finite element model of station-tunnel transition section structure and its dynamic analysis are established. Seismic performance of the structure under three different levels of earthquake is investigated mainly based on internal forces and displacement response of pillars and sidewalls, stress response of station-tunnel transition wall and integral deformation.Resultsshow that dynamic tensile and compressive stresses occur at both the top and bottom of center pillars. Stress concentration appears at the junction of sidewalls and floors, as well as around the tunnel portals on the station-tunnel transition wall.Deformation of sidewalls vertically increases from the bottom up. Due to the complicated forces, center pillars show “S”type failure mode. As a result, appropriate reinforcement measures should be taken against these weaknesses in actual project. The related conclusions can provide theoretical basis and reference for seismic design of underground engineering research.