Numerical Analysis of Deformation Control of Deep Foundation Pit in Ulanqab City

The deformation of a deep foundation pit in Ulanqab city was analyzed by in situ monitoring and numerical simulation data. First, a limit equilibrium method was used to evaluate the stability of foundation pit under non-supporting and ribbed plate anchored retaining wall support. The results show that the ribbed plate anchored retaining wall support could control the soil deformation effectively in deep foundation pit. Additionally, a three-dimensional finite difference model of excavation zone and reinforcement structure was established using FLAC3D software to simulate the excavation of deep foundation pit. The simulation results were verified by monitoring field data. The simulation results show that all the bolts are in the tension state, and the maximum axial force is located at the end of the bolt, with a value of 46.4 kN. Foundation pit excavation is a continuous stress release process, making the rock and soil of side wall of foundation pit slide towards the free surface. The largest deformation is 4.0 mm, near the side wall of foundation pit, consistent with the deformation monitoring results.