Abstract: With the rapid development of urbanization, many subway projects are being planned along subway lines. The construction dewatering and excavation of subway foundations will inevitably cause changes in the soil boundary conditions around the subway structure. The seismic performance of subway structures is also a key research subject. In order to study the impact of foundation excavation and dewatering on the surrounding environment and the seismic performance of the station structure itself, the risk sources of the station deep excavations, the environmental risk sources of the station excavations surroundings, and the characteristics of the station structure under seismic loads were analyzed by using the Qixing software, a 3D seepage analytical software Visual Modflow, and the finite element software Midas GTS NX. The analysis results indicates that the permeability of the soil is the main factor affecting the settlement of surrounding buildings and structures caused by dewatering inside the excavation. The settlement of surrounding buildings and structures is directly proportional to the radial distance from the excavation; The interlayer displacement between the middle plate and the bottom plate inside the subway station structure is greater than the interlayer displacement between the middle plate and the top plate.

Key words: Subway Deep Excavation, Dewatering, Boundary Conditions, Structural Seismic Resistance, Settlement Level