基坑开挖对下卧既有盾构隧道的变形影响研究
发布时间：2018-07-13 19:19
【摘要】：随着城市交通量大量增长，地铁成为解决交通堵塞的一个有效的手段，目前我国已经有大量城市开通地铁或者正在进行地铁建设了。同时，城市的地面发展也是快速发展，不可避免的出现大量在地铁隧道上建设的基坑工程。上方的基坑和下方的既有隧道相互影响，基坑开挖必然对既有下方地铁盾构隧道造成影响，将会影响到地铁的安全运营。目前，关于基坑开挖对既有下方地铁盾构隧道变形的影响研究还不够完善，本文采用有限元软件Midas/GTS进行数值模拟的方法，研究基坑开挖对下方隧道造成变形的规律。本文主要做了以下工作： （1）介绍了本文的研究背景，总结了关于基坑开挖对下卧既有盾构隧道变形影响的研究现状，提出了本文的研究方法和解决的问题。 （2）分析了基坑开挖引起土体变形的机理，总结归纳了基坑开挖引起的周围土压力计算方法、基坑隆起的回弹量计算方法、残余应力的计算方法以及基坑变形的影响因素；总结了基于弹性地基梁理论的基坑开挖对下卧隧道的变形计算方法，，给出了下卧隧道的附加应力、竖向变形、扰度、弯矩、转角以及剪力的计算方法和解析解。 （3）通过Midas/GTS的数值模拟分析，对基坑开挖过程造成隧道变形影响进行模拟分析，分别对各施工阶段、不同基坑尺寸、不同基坑与隧道相对位置、不同基坑开挖方法、不同工程地质条件对隧道的变形影响进行分析。分析结果表明：隧道的位移以竖向位移为主，变形最大处出现在基坑开挖至底部时；基坑宽度、垂直距离、轴线相对距离对隧道变形影响显著，呈线性关系；垂直距离、轴线相对距离对隧道水平位移影响不大；基坑沿隧道纵向的长度对隧道变形影响不大；基坑的支护和支撑结构能减小隧道的变形；基坑分块开挖能减小隧道的最大竖向位移，在底板浇筑前，能缩短隧道最大变形的暴露时间；工程地质条件对隧道变形有显著影响，地质条件越差，隧道产生的变形越大。 （4）总结归纳了在既有下卧隧道的基坑开挖工程保护措施和工程监测技术。
[Abstract]:With the rapid growth of urban traffic, subway has become an effective means to solve traffic jams. At present, a large number of cities in China have opened the subway or are carrying out subway construction. At the same time, the ground development of the city is also rapid development, inevitably there are a large number of foundation pit construction on the subway tunnel. The foundation pit above and the existing tunnel below affect each other, and the excavation of foundation pit will inevitably affect the shield tunnel under the existing subway, which will affect the safe operation of the subway. At present, the research on the influence of foundation pit excavation on the deformation of shield tunnel under existing subway is not perfect. In this paper, the method of finite element software Midas / GTS is used to simulate the deformation of underground tunnel caused by excavation of foundation pit. The main work of this paper is as follows: (1) the research background of this paper is introduced, and the research status of the influence of foundation pit excavation on the deformation of existing shield tunnel is summarized. The research methods and the problems solved in this paper are put forward. (2) the mechanism of soil deformation caused by foundation pit excavation is analyzed, and the calculation method of surrounding earth pressure caused by foundation pit excavation and the calculation method of springback amount of foundation pit uplift are summarized. The calculation method of residual stress and the influencing factors of foundation pit deformation are summarized, and the calculation method of foundation pit excavation deformation to underside tunnel based on elastic foundation beam theory is summarized, and the additional stress, vertical deformation, disturbance, bending moment of subhorizontal tunnel are given. (3) through the numerical simulation analysis of Midas / GTS, the influence of tunnel deformation caused by excavation process is simulated and analyzed. Different relative positions of foundation pit and tunnel, different excavation methods and different engineering geological conditions are used to analyze the influence of tunnel deformation. The results show that the displacement of the tunnel is mainly vertical displacement, and the maximum deformation occurs when the foundation pit is excavated to the bottom, the width, vertical distance and relative distance of axis have significant influence on the tunnel deformation, and the vertical distance is linear. The relative distance of axis has little effect on the horizontal displacement of the tunnel; the longitudinal length of the foundation pit has little effect on the tunnel deformation; the supporting and supporting structure of the foundation pit can reduce the deformation of the tunnel; and the maximum vertical displacement of the tunnel can be reduced by the block excavation of the foundation pit. Before the bottom slab is cast, the exposure time of the maximum deformation of the tunnel can be shortened, and the engineering geological conditions have a significant effect on the tunnel deformation, and the worse the geological conditions are, The deformation caused by the tunnel is greater. (4) the protection measures and engineering monitoring techniques of foundation pit excavation in the existing underside tunnel are summarized.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U452.11;U231
本文编号：2120479
[Abstract]:With the rapid growth of urban traffic, subway has become an effective means to solve traffic jams. At present, a large number of cities in China have opened the subway or are carrying out subway construction. At the same time, the ground development of the city is also rapid development, inevitably there are a large number of foundation pit construction on the subway tunnel. The foundation pit above and the existing tunnel below affect each other, and the excavation of foundation pit will inevitably affect the shield tunnel under the existing subway, which will affect the safe operation of the subway. At present, the research on the influence of foundation pit excavation on the deformation of shield tunnel under existing subway is not perfect. In this paper, the method of finite element software Midas / GTS is used to simulate the deformation of underground tunnel caused by excavation of foundation pit. The main work of this paper is as follows: (1) the research background of this paper is introduced, and the research status of the influence of foundation pit excavation on the deformation of existing shield tunnel is summarized. The research methods and the problems solved in this paper are put forward. (2) the mechanism of soil deformation caused by foundation pit excavation is analyzed, and the calculation method of surrounding earth pressure caused by foundation pit excavation and the calculation method of springback amount of foundation pit uplift are summarized. The calculation method of residual stress and the influencing factors of foundation pit deformation are summarized, and the calculation method of foundation pit excavation deformation to underside tunnel based on elastic foundation beam theory is summarized, and the additional stress, vertical deformation, disturbance, bending moment of subhorizontal tunnel are given. (3) through the numerical simulation analysis of Midas / GTS, the influence of tunnel deformation caused by excavation process is simulated and analyzed. Different relative positions of foundation pit and tunnel, different excavation methods and different engineering geological conditions are used to analyze the influence of tunnel deformation. The results show that the displacement of the tunnel is mainly vertical displacement, and the maximum deformation occurs when the foundation pit is excavated to the bottom, the width, vertical distance and relative distance of axis have significant influence on the tunnel deformation, and the vertical distance is linear. The relative distance of axis has little effect on the horizontal displacement of the tunnel; the longitudinal length of the foundation pit has little effect on the tunnel deformation; the supporting and supporting structure of the foundation pit can reduce the deformation of the tunnel; and the maximum vertical displacement of the tunnel can be reduced by the block excavation of the foundation pit. Before the bottom slab is cast, the exposure time of the maximum deformation of the tunnel can be shortened, and the engineering geological conditions have a significant effect on the tunnel deformation, and the worse the geological conditions are, The deformation caused by the tunnel is greater. (4) the protection measures and engineering monitoring techniques of foundation pit excavation in the existing underside tunnel are summarized.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U452.11;U231
【参考文献】
相关期刊论文 前10条
1 林永国,廖少明,刘国彬;地铁隧道纵向变形影响因素的探讨[J];地下空间;2000年04期
2 陈郁,李永盛;基坑开挖卸荷引起下卧隧道隆起的计算方法[J];地下空间与工程学报;2005年01期
3 曾远,李志高,王毅斌;基坑开挖对邻近地铁车站影响因素研究[J];地下空间与工程学报;2005年04期
4 张云军;宰金珉;王旭东;常银生;戚科骏;;隧道开挖对临近桩基影响的二维数值分析[J];地下空间与工程学报;2005年06期
5 李家平;;基坑开挖卸载对下卧地铁隧道影响的数值分析[J];地下空间与工程学报;2009年S1期
6 刘国彬,侯学渊;软土基坑隆起变形的残余应力分析法[J];地下工程与隧道;1996年02期
7 宋玮;唐寿高;范益群;;某高层公寓工程对后续地铁隧道影响的三维分析[J];地下工程与隧道;2004年04期
8 毛朝辉;刘国彬;;基坑开挖引起下方隧道变形的数值模拟[J];地下工程与隧道;2005年04期
9 李大勇,张土乔,龚晓南;深基坑开挖引起临近地下管线的位移分析[J];工业建筑;1999年11期
10 李亚,刘国彬,刘纯洁;地层补偿法新析[J];地下工程与隧道;2000年01期
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