Numerical Analysis Of Deep Excavation Structure And Site Monitoring

The present study mainly demonstrated the development of foundation pit theory and the simulated application of numerical analysis method in the process of pit excavation. Based on previous researches, the present study employed FLAC3D to carry out simulate analysis of deep foundation pit data. In the process of pit excavation, the mechanical and deformation law of stress field, displacement field, and retaining structure system was concluded. Moreover, the present study conducted field measurement and contrast analysis of retaining structure's stress-strain and soil deformation. The contents and conclusions of the present study were listed as follows.1. The present study explained the development of foundation pit systematically, introduced the application of numerical analysis in foundation pit engineering simulation, and elaborated the definite difference method and FLAC. In the process of pit excavation, the retaining structure's stress-strain and soil deformation were studied, while in the process of data simulation, the interaction of seepage field and stress field was considered, and the influence of asynchrony of excavation and precipitation was also considered as well. As a result, four simulation plans were summarized.2. By establishing the definite-difference model,3D simulation of the foundation pit structure system was made. The result showed that the retaining structure's deformation was relatively small, and displacement distribution law of the retaining pile was appeared like a curve, which could be summarized as "small in two ends, while big in the middle". The main internal force of pile body was increased with the depth increase of foundation pit. Additionally, the design of top beam and inner supporting was beneficial to the retaining structure.3. The field monitoring outline was made according to the practical circumstances. After the collection and analysis of the monitoring data, the laws of pile body and retaining stress' internal force, and displacement change were concluded. The data showed that in the process of pit excavation, pressure was changed continuously with a relatively low value, and the internal stress of retaining structure was controllable. Meanwhile, contrastive analysis of the monitoring result and simulation result could be used to confirm the rationality and correction of simulation analysis.4. Finally, the present study compared the simulation result and the real field measurement result. Then, possible factors that influenced the simulation result and real field measurement results were put forward. Furthermore, theories and aims of the optional retaining structure were provided, which could give some implications to the further research of this studying field.