Analysis of the influence of subway entrance excavation on tunnel and adjacent buildings

With the rapid development of urban subway transit construction, the construction of subway entrance and exit accessory structure in densely populated areas and near buildings is gradually increasing. Based on the open-cut foundation pit project at the entrance and exit of subway R3 line in Jinan city, this paper adopted MADIS GTS/NX 3D finite element analysis software to conduct finite element analysis on the connection tunnel and adjacent buildings by subway entrance and exit foundation pit excavation, and analyzed the displacement change trend of foundation pit excavation on the underground tunnel and building. The results show that the horizontal displacement of the connection area between the tunnel and the foundation pit is small, while the vertical displacement of the tunnel is relatively large, with a maximum value of 3.58mm. The settlement at the corner of the building adjacent to the foundation pit is relatively large, and the maximum settlement value is 3.03mm. It is in good agreement with the measured data and meets the requirement of deformation control. This study provides reference for the foundation pit engineering of subway entrance and exit of similar adjacent buildings.