Simulation Analysis On Construction Of Deep Foundation Pit Of Xiaoguishan And Hankou Railway Station Of No.2 Subway In WuHan City

With the increase in running metro lines, effects on surrounding environments and safety of subway station deep excavation are paid more attention. Not only space effect of foundation but also effect of dewatering is often ill considered in many designs at present, which make many hidden troubles to the safety of excavation.The paper is carried out against a background of Xiaoguishan and Hankou subway station excavation of Wuhan No.2 metro. The useful conclusion is obtained from the analysis of the simulation results which be reached through calculation of numerical simulation.Xiaoguishan station excavation is simulated on 2-d numerical and 3-d numerical simulation respectively by using ABAQUS. The mid-span cross-section is the most dangerous cross section. The internal force and deformation and soil deformation of retaining structure on 2-d numerical simulation are similar to the 3-d numerical simulation's expect figure which indicate excavation's space effect.By using program Plaxis, the internal force and deformation of retaining structures of Hankou Rail subway station excavation is analyzed. And the general rules of the internal force and deformation and soil deformation of retaining structure of subway station excavation with dewatering are given. With depth of single dewatering well going down, water discharge and seepage velocity increase, deformation of soil and retaining wall decrease. With space between two well increasing, ground settlement, displacement and bending moment of retaining wall decrease. Internal force and displacement of retaining wall of dewatering around excavation is less than dewatering in excavation. With thickness of diaphragm wall enlarged, displacement of retaining wall and soil is inhibited significantly, but it doesn't work on seepage velocity and ground settlement. Seepage velocity is inhibited significantly with length of diaphragm wall enlarged. Displacement of retaining wall is inhibited significantly by brace pre-axial force, which is of no effect on bending moment of retaining wall. Some conclusions and advices are provided to the retaining wall and dewatering plan of the stations in this paper.