城市地下空间开发和高层建筑的出现产生了大量的深基坑工程，而城市深基坑一般都处在密集的建筑群中，施工场地狭窄，有些基坑甚至与己有建筑物或构筑物的基础紧紧相邻。在富水地区基坑降水是基坑工程的一项重要内容，基坑工程降水对周围地表沉降的影响己引起广泛关注，地面沉降对环境和工程危害极大，它将导致地面产生裂缝和邻近建筑物基础下沉、倾斜和开裂。在考虑基坑开挖降水时，如何正确估算邻近建筑的沉降对基坑支护设计和施工有重要的意义。 本文在考虑降水环境下将基坑、支护结构及邻近建筑物放在一个系统中进行研究，运用大型工程软件FLAC3D，分别对降水前、后深基坑开挖、支护的全过程进行了数值模拟。通过降水前、后邻近建筑物在不同距离条件下、地下连续墙不同入土深度支护情况下以及不同降水深度环境下的对比模拟分析，引入了降水对邻近建筑沉降的修正系数，通过监测点的曲线分析得到了修正系数随建筑物距离和降水深度变化的函数关系式，找到了降水引起邻近建筑不均匀沉降及绝对沉降的发展变化规律，确定了降水对邻近建筑影响的范围及有效约束邻近建筑沉降的连续墙入土深度范围。 论文的研究成果对于考虑基坑降水影响后建筑物的沉降计算开辟了新的途径，同时对于富水地区深基坑工程设计和施工提供了重要的指导意义。

The development of underground space and the emergence of more high-rise buildings in urban areas have made more and more deep pits engineering, Dense buildings generally surround the deep foundation pits in urban areas with narrow construction site. Sometimes, the foundation pit is very close to the foundations of the nearest buildings or structures. It is a very important part in foundation pit engineering to dewater in high groundwater level region. The surface settlement caused by dewatering and excavation has been noticed widely. Surface settlement damages the environment and construction badly. It will make the surface crack and make buildings settlement or incline. It is very important significance for foundation pit design and construction to how to estimate correctly the settlement of the adjacent buildings or structures in considering the case of dewatering In this thesis, an integrated system consisting of dewatering, deep foundation pit, supporting structure and adjacent structure is studied, and the excavation process of a deep foundation pit under the condition of dewatering and no dewatering is simulated by means of large-scale engineering software-FLAC3D.It define a correction factor about adjacent buildings settlement by comparison of simulation analysis considering dewatering and ignoring dewatering under the condition of different distance from buildings to foundation pit, different underground retaining wall length inserting soil and different dewatering depth. Through the monitoring point curve analysis, we get relationship between correction factor and the distance from building to foundation pit and the depth of dewatering. By the correction factor, we find adjacent buildings uneven and absolute settlement discipline caused by dewatering, make sure the damaged bound caused by dewatering and determine underground retaining wall length inserting soil to effective restrict adjacent buildings settlement. The consequent makes a new way to calculate adjacent buildings settlement in the case of dewatering and it provides an important guiding significance to deep foundation engineering design and construction in high groundwater level.