Numerical Simulation of Shield Tunnel Passing under the Existing Subway Station

Based on the shield tunnel of a newly constructed line that crosses underneath the existing subway station in Beijing,concerning on the stress release method,step excavation and the pre-reinforced construction of the newly constructed line,the displacement influence is analyzed by a three-dimensional finite-difference program FLAC3D.By means of FLAC3D simulation a layer-structure model is established,and the Mohr-Coulomb criterion is used to describe the soil.Besides,the tunnel structure and the existing subway station simulate by the structural elements,and the link elements are used to simulate the settlement slot of the existing subway station.The deformation of the existing subway station is predicted,and the achieved results can provide references to the safety evaluation of the adjacent subway station.