本文以某地铁车站深基坑为工程背景，分别从理论分析、数值模拟和现场监测三个方面开展论文的研究，主要工作如下： （1）在原有理论的基础上，分析了深基坑开挖引起地层变形的机理，并总结了影响基坑变形的主要因素。研究表明，基坑开挖本身作为一个卸荷过程，在开挖的过程中，荷载不断减小，造成坑底回弹，基坑两侧土体在压力差的作用下向基坑内移动从而引起地层变形。影响基坑变形的因素众多，主要包括工程地质，水文地质等固有因素，基坑支护结构形式及支护结构刚度等设计因素以及施工方法，施工周期等施工因素。 （2）基于反分析原理，建立了围护结构水平位移与各土层弹性模量之间的非线性映射关系，采用了不带交叉项的二次函数作为各土层弹性模量的反演函数，分两步对各土层弹性模量进行反演。第一步，以多重响应面函数中的11个参数为可变目标，并结合FLAC3D软件模拟围护结构的水平位移，反演出各参数值。第二步以各土层的弹性模量为可变目标，基于最小二乘法，采用非线性GRG方法，向前派生求解，反演得到各土层的弹性模量。 （3）利用反演得到的弹性模量进行数值模拟，分析了不同工况、不同迭代次数、不同距离时围护结构及桥桩的位移变化特征。结果表明，采用第三次反分析进行计算的模拟曲线较好地模拟出曲线的形态，包括峰值大小、位置及转折点；随着迭代次数的增加，模拟精度不断提高，至第三次迭代时，已满足精度要求。 （4）利用FLAC3D软件对比分析了采取袖阀管预加固措施与未采取预加固措施的区别。研究表明，采取预加固注浆措施可以有效地降低桥桩的水平位移，由于预注浆加固作用，桥桩水平位移曲线在深度15m左右缩减为零。

This paper takes the subway station of as the project background, and the thesis is studied in three aspects: theoretical analysis, numerical simulation and field monitoring. The main work is as follows: (1)On the basis of the original theory, the mechanism of stratum deformation caused by deep foundation pit excavation is analyzed, and the main factors affecting the deformation of foundation pit are summarized. The research shows that the excavation itself is a unloading process. In the process of excavation, the load decreases continuously, resulting in the rebound of the bottom of the pit. The soil on both sides of the foundation pit moves to the foundation pit under the effect of pressure difference and causes the formation deformation. There are many factors affecting the deformation of the foundation pit, including the inherent factors of engineering geology, hydrogeology, the design factors of the form of the foundation pit supporting structure and the stiffness of the supporting structure, and the construction factors, such as the construction method and the construction period. (2) Based on the reverse analysis principle, the nonlinear mapping relation between the horizontal displacement of the diaphragm wall and the elastic modulus of each soil layer is established, and the two function without cross term is used as the inversion function of the elastic modulus of each soil layer, and the elastic modulus of each soil layer is retrieved in two steps. The first step is to use the 11 parameters of the multiple response surface function as the variable target, and simulate the horizontal displacement of the diaphragm wall with flac3d software, and reproduce the parameters values. In the second step, the elastic modulus of each soil layer is variable. Based on the least square method, the nonlinear grg method is used to derive the elastic modulus of each soil layer. (3)The numerical simulation of the elastic modulus obtained by the inversion is used to analyze the displacement characteristics of the diaphragm wall and the bridge pile with different working conditions, different iterations and different distances. The results show that the simulated curve of the second inverse analysis is better to simulate the shape of the curve, including the peak value, the position and the turning point. With the increase of the number of iterations, the accuracy of the simulation is improved continuously, and the precision requirement has been satisfied to the third iteration. (4) Using flac3d software to compare and analyze the difference between sleeve valve pipe pre reinforcement and pre reinforcement measures. The study shows that the horizontal displacement of the bridge pile can be effectively reduced by the pre reinforcement grouting. The horizontal displacement curve of the bridge pile is reduced to zero at about 15m due to the pre grouting reinforcement.