Research On Deformation Monitoring And Numerical Simulation Of Soil Nail Wall Pile Anchor Support In Deep Foundation Pit

With the development of urbanization, deep excavation in China has increased every year, and the problems in deep excavation design are more and more serious. In order to ensure the secure of surrounding environment and building during foundation pit excavation,and economical economy, the deep research for the problem of foundation excavation has become uppermost priority.In this paper, based on the Lanzhou City apartment building of airport project, selection and design are applied to supporting scheme of deep foundation excavation. FLAC3 D is used to simulate the excavation process of deep foundation excavation, while, the simulation results are compared with the actual monitoring data. The following findings can be made:(1)In the soil nail pile-anchor supporting, after the construction of lower part of the anchor, there are a more significant role in limiting to the horizontal and vertical displacement of the pile; During the excavation, the amount of horizontal displacement of pile is proportional to the depth of excavation, namely, the greater the amount excavated the larger of the horizontal displacement.(2) During the construction process, we monitor the horizontal and vertical displacement, the development of pile of the top of soil nailing structure. The results show:the construction of pile anchor cable structure has certain restrictions to the deformation of top of the hill horizontal and vertical displacement.(3) Using FLAC3 D finite difference software to simulate numerical analysis of excavation process, obtained the slope deformation of excavation of supporting structure and the settlement. Calculation shows that the numerical results agree well with the measured results, and the design and construction of the supporting structure are safe and reasonable,which verifies that the anchor pile-soil nailing structure is applicable in Lanzhou region.The method used that is combining the numerical analysis and engineering examples in thesis to provide a reference for future similar engineering geological conditions in the loess plateau deep excavation.