Analysis Of Influence Of New Station Construction On Existing Underground Structures

In this paper,based on the parallel transfer station of Shenzhen Metro Line 11 and Metro Line 1,a numerical model is established by using FLAC3 D software.A new method to simulate the connection between new and old structures by contact surface element is presented.The correctness of the model isproved by comparison between the numerical simulation results and the existing station and its envelope structure test results.At the same time,the influence of the foundation pit construction of the new station on the deformation of existing structures is summarized.Comparison of different excavation methods,different excavation step,whether the increase of lead pipe shed support,increase lateral support stiffness and different enclosure grouting depth under different conditions,both the deformation of structure,using the top-down method,excavation length 6m,increase super support,increase the lateral roof before 20% rate of reinforcement and retaining the grouting depth for the bottom floor of these measures can take into account the economy under the premise of minimizing the deformation of existing structure.By contrast,the new station maintenance structure,the existing station in each excavation step relative settlement,obtained the maximum relative settlement to get rid of the upper and lower holes,put forward a set of temporary vertical support reinforcement and other measures to control the relative settlement.