Three Dimensional Numerical Analyses And A Field Experiment Verification Of The Deformation Of Retaining Structures For Hollow Foundation Pits Based On Additional Earth Pressures

The deformation analysis of retaining structure is the main content of retaining structure design.According to the different safety level of foundation pit,the deformation of the retaining structure must be within a certain limit.Now,the method of calculating the deformation of support structure in engineering is the elastic reaction method,however this method is not very accurate and cannot reflect the shortcomings of the spatial effect and applicability of the foundation pit.In order to further improve the analysis ability of foundation pit deformation,in this paper,the site model test and numerical simulation were used to analyze the three-dimensional deformation of the retaining structure and its effect on Actual soil pressure and additional soil pressure.The following works were carried out:1 A site model test was carried out.Test measurements include: active and positive soil pressure of pile side、Strain of pile、displacement of pile top.2.ABAQUS was used to simulate the excavation and overload of the experiment.The influence of overload on the deformation of different position supporting structures and the influence of overload on the displacement of the support structure were studied.The distribution and variation of soil pressure in each working condition wall were analyzed.3.The influence of planar size and excavation depth on the spatial effect of foundation pit support structure was analyzed using ABAQUS.4 The finite element model of the real pile is established,and the different deformation rules and calculation results are compared between the equivalent bending-resistant stiffness wall and the real pile model in the excavation of foundation pit.The proposed method for calculating the equivalent wall model was proposed.5.The 3D analysis program TDAP was arranged.Using this program,the spatial effect of the foundation pit of different plane size was also studied.Based on the shortcoming of the program,the further improvement direction of the program was proposed.6.The data of site model test were analyzed,the overall deformation rule of the retaining structure and the soil pressure and the distribution on the pile side were analyzed.