论文总字数：24167字

摘 要

随着岩土工程技术的发展，基坑工程有着不断向深、大基坑发展的趋势，由于深、大基坑自身变形影响大并且对环境的影响也较为强烈，基坑及周边环境的安全问题也就愈发重要。

本文将依托南京中宝电子有限公司功率MOS-D二极管研发生产基地项目，依据基坑状况、周边环境条件以及岩土工程勘察报告对多家设计单位提供的共六份基坑支护设计方案进行比选，并根据基坑监测方案，结合监测信息反馈，进行基坑施工监控分析和数值模拟。

首先通过对六份设计方案分别进行定性分析，确定了其对拟建基坑的适应性情况，然后对安全性、经济性、施工工期及难易程度等条件进行比较，选出了其中较为符合各项要求的方案，并根据工程和施工的实际情况进行了具体的修改。在基坑监测项目中选取了沉降、测斜、立柱沉降和支撑轴力这四项，通过对监测数据进行时间上和空间上的比对，对施工过程中基坑支撑及周边环境的变形规律和机理进行了分析。最后通过学习使用PLAXIS软件对基坑开挖过程模拟，进行了有限元分析。

本文所介绍的工程项目尚未完成施工，但是基本一直处于稳定状态。通过对此项目的介绍，也将会对以后的基坑工程建设有一定的借鉴意义。

关键词：深大基坑，支护设计，方案比选，监测分析，有限元分析

ABSTRACT

With the development of geotechnical engineering technology, the foundation pit project has a tendency of continuous development towards deep and large foundation pits. Due to the large impact of deep and large pit excavations and their strong impact on the environment, safety of foundation pits and surrounding environment The problem is even more important.

This article will rely on Nanjing Zhongbao Electronics Co., Ltd. power MOS-D diode research and development production base project, based on the pit status, surrounding environmental conditions and geotechnical engineering survey reports on a total of six design support units provided by the foundation pit support design program Comparison and selection, and in accordance with the monitoring program of the foundation pit, combined with monitoring information feedback, monitoring and analysis of the construction of the foundation pit.

Firstly, through qualitative analysis of the six design plans, the suitability of the proposed design to the proposed foundation pit was determined. Then the safety, economical efficiency, construction duration, and the degree of difficulty were compared, and the more suitable ones were selected. The requirements of the program, and in accordance with the actual situation of the project and the construction of a specific modification. In the foundation pit monitoring project, the four items of settlement, inclinometer, column settlement and supporting axial force were selected. Through the time and space comparison of the monitoring data, the deformation of the foundation pit support and surrounding environment during the construction process was studied. And the mechanism was analyzed. Finally, by using PLAXIS software to simulate the excavation process of the foundation pit, finite element analysis was performed.

The project described in this article has not yet completed construction, but it has basically remained stable. Through the introduction of this project, it will also have some reference significance for the future construction of the foundation pit.

KEY WORDS: deep foundation pit, support design, comparison and selection of options, monitoring analysis, finite element analysis

目 录

摘 要 I

ABSTRACT II

第一章 总体概况 1

1.1工程概况 1

1.1.1环境概况 1

1.1.2工程设计概况 3

1.2工程地质概况 4

1.2.1地形地貌 4

1.2.2工程地质概况 4

1.3水文地质概况 6

1.3.1地表水 6

1.3.2地下水类型及其补排特征 6

1.4监测概况 6

1.4.1监测目的 7

1.4.2监测依据 7

1.4.3监测方案编制原则 8

第二章 基坑支护方案比选 9

2.1基坑概况 9

2.2地质条件评价 9

2.2.1场地稳定性和适宜性评价 9

2.2.2场地不良地质作用及特殊性岩土 9

2.2.3基坑开挖范围内的土层 10

2.2.4基坑开挖深度范围内地下水 10

2.3基坑支护方案比选 10

2.3.1支护方案一 10

2.3.2支护方案二 11

2.3.3支护方案三 12

2.3.4支护方案四 13

2.3.5支护方案五 13

2.3.6支护方案六 14

2.3.7方案分析与对比 15

2.3.8方案选择 16

第三章 施工监控分析 17

3.1本工程重难点及风险点分析 17

3.2监测项目 17

3.3监测成果分析 22

3.3.1现场巡查 22

3.3.2沉降监测点分析处理 23

3.3.3深层水平位移（测斜）监测分析 26

3-3-4立柱竖直位移监测分析 30

3.3.5支撑轴力监测分析 31

3.3.6水位监测分析 31

第四章 PLAXIS有限元分析 33

4.1PLAXIS软件简介 33

4.2数值模拟 33

4.2.1模型建立 33

4.2.2工序设计 34

4.3模拟结果及分析 35

4.3.1总体变形 35

4.3.2水平位移 36

4.3.3竖向位移 36

4.3.4有效应力 37

第五章 总结 38

致 谢 40

参考文献 41

第一章 总体概况

1.1工程概况

拟建南京中宝电子有限公司功率MOS-D二极管研发生产基地项目，场地位于南京市江宁江宁科学园湖山路733号。拟建建筑物概况如表1.1。

表1.1