The Impact of Different Excavation Support Structures on the Deformation and Stability of Adjacent Station and Tunnels

This study uses the finite element software Midas GTS NX (2019), combined with actual engineering projects, to establish numerical models and analyze the impact of different support types (pile-anchor support and double-row pile support) on the excavation of foundation pits near metro station tunnels. The results indicate that under both support methods, the vertical displacement of the tunnel is the greatest at the interface between the station and the tunnel, with greater vertical displacement occurring under double-row pile support. Under pile-anchor support, the horizontal displacement of the tunnel reaches its maximum value during the sixth excavation stage, while under double-row pile support, the horizontal displacement increases steadily, and the overall displacement is small. The horizontal displacement under pile-anchor support is significantly greater than that under double-row pile support. For the station, the maximum vertical displacement under pile-anchor support is smaller than that under double-row pile support. The horizontal displacement under pile-anchor support exhibits a linear change, while under double-row pile support, the displacement continuously increases from the end of the foundation pit farther from the excavation to the end closer to it. The model tests are consistent with the numerical simulation results, verifying the correctness of the numerical simulation. This study can provide references for relevant engineering projects to ensure the safety and stability of metro structures.