【摘要】：隨著城市交通量大量增長(zhǎng)，地鐵成為解決交通堵塞的一個(gè)有效的手段，目前我國(guó)已經(jīng)有大量城市開(kāi)通地鐵或者正在進(jìn)行地鐵建設(shè)了。同時(shí)，城市的地面發(fā)展也是快速發(fā)展，不可避免的出現(xiàn)大量在地鐵隧道上建設(shè)的基坑工程。上方的基坑和下方的既有隧道相互影響，基坑開(kāi)挖必然對(duì)既有下方地鐵盾構(gòu)隧道造成影響，將會(huì)影響到地鐵的安全運(yùn)營(yíng)。目前，關(guān)于基坑開(kāi)挖對(duì)既有下方地鐵盾構(gòu)隧道變形的影響研究還不夠完善，本文采用有限元軟件Midas/GTS進(jìn)行數(shù)值模擬的方法，研究基坑開(kāi)挖對(duì)下方隧道造成變形的規(guī)律。本文主要做了以下工作： （1）介紹了本文的研究背景，總結(jié)了關(guān)于基坑開(kāi)挖對(duì)下臥既有盾構(gòu)隧道變形影響的研究現(xiàn)狀，提出了本文的研究方法和解決的問(wèn)題。 （2）分析了基坑開(kāi)挖引起土體變形的機(jī)理，總結(jié)歸納了基坑開(kāi)挖引起的周圍土壓力計(jì)算方法、基坑隆起的回彈量計(jì)算方法、殘余應(yīng)力的計(jì)算方法以及基坑變形的影響因素；總結(jié)了基于彈性地基梁理論的基坑開(kāi)挖對(duì)下臥隧道的變形計(jì)算方法，，給出了下臥隧道的附加應(yīng)力、豎向變形、擾度、彎矩、轉(zhuǎn)角以及剪力的計(jì)算方法和解析解。 （3）通過(guò)Midas/GTS的數(shù)值模擬分析，對(duì)基坑開(kāi)挖過(guò)程造成隧道變形影響進(jìn)行模擬分析，分別對(duì)各施工階段、不同基坑尺寸、不同基坑與隧道相對(duì)位置、不同基坑開(kāi)挖方法、不同工程地質(zhì)條件對(duì)隧道的變形影響進(jìn)行分析。分析結(jié)果表明：隧道的位移以豎向位移為主，變形最大處出現(xiàn)在基坑開(kāi)挖至底部時(shí)；基坑寬度、垂直距離、軸線相對(duì)距離對(duì)隧道變形影響顯著，呈線性關(guān)系；垂直距離、軸線相對(duì)距離對(duì)隧道水平位移影響不大；基坑沿隧道縱向的長(zhǎng)度對(duì)隧道變形影響不大；基坑的支護(hù)和支撐結(jié)構(gòu)能減小隧道的變形；基坑分塊開(kāi)挖能減小隧道的最大豎向位移，在底板澆筑前，能縮短隧道最大變形的暴露時(shí)間；工程地質(zhì)條件對(duì)隧道變形有顯著影響，地質(zhì)條件越差，隧道產(chǎn)生的變形越大。 （4）總結(jié)歸納了在既有下臥隧道的基坑開(kāi)挖工程保護(hù)措施和工程監(jiān)測(cè)技術(shù)。
[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.
【學(xué)位授予單位】：華南理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U452.11;U231

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 林永國(guó),廖少明,劉國(guó)彬;地鐵隧道縱向變形影響因素的探討[J];地下空間;2000年04期

2 陳郁,李永盛;基坑開(kāi)挖卸荷引起下臥隧道隆起的計(jì)算方法[J];地下空間與工程學(xué)報(bào);2005年01期

3 曾遠(yuǎn),李志高,王毅斌;基坑開(kāi)挖對(duì)鄰近地鐵車站影響因素研究[J];地下空間與工程學(xué)報(bào);2005年04期

4 張?jiān)栖?宰金珉;王旭東;常銀生;戚科駿;;隧道開(kāi)挖對(duì)臨近樁基影響的二維數(shù)值分析[J];地下空間與工程學(xué)報(bào);2005年06期

5 李家平;;基坑開(kāi)挖卸載對(duì)下臥地鐵隧道影響的數(shù)值分析[J];地下空間與工程學(xué)報(bào);2009年S1期

6 劉國(guó)彬,侯學(xué)淵;軟土基坑隆起變形的殘余應(yīng)力分析法[J];地下工程與隧道;1996年02期

7 宋瑋;唐壽高;范益群;;某高層公寓工程對(duì)后續(xù)地鐵隧道影響的三維分析[J];地下工程與隧道;2004年04期

8 毛朝輝;劉國(guó)彬;;基坑開(kāi)挖引起下方隧道變形的數(shù)值模擬[J];地下工程與隧道;2005年04期

9 李大勇,張土喬,龔曉南;深基坑開(kāi)挖引起臨近地下管線的位移分析[J];工業(yè)建筑;1999年11期

10 李亞,劉國(guó)彬,劉純潔;地層補(bǔ)償法新析[J];地下工程與隧道;2000年01期

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