發(fā)布時(shí)間：2019-02-14 20:14

【摘要】：我國(guó)東部沿海地區(qū)經(jīng)濟(jì)發(fā)展迅速,城市快速發(fā)展對(duì)土地資源的需求與日俱增,然而有限的土地資源越來(lái)越成為城市發(fā)展的重要限制因素,所以地下空間的開(kāi)發(fā)和利用是當(dāng)今城市發(fā)展的主流趨勢(shì),尤其是地鐵的建設(shè)已經(jīng)成為各大城市交通發(fā)展的熱點(diǎn)方向。我國(guó)東南沿海城市屬于典型的軟土地基,工程地質(zhì)狀況復(fù)雜,施工難度大,施工安全隱患大,因此對(duì)軟土地區(qū)地鐵車(chē)站深基坑支護(hù)結(jié)構(gòu)變形的研究具有重要的實(shí)際意義。本文依托無(wú)錫地鐵2號(hào)線梁溪大橋地鐵車(chē)站深基坑工程,運(yùn)用現(xiàn)場(chǎng)監(jiān)測(cè)和數(shù)值分析的方法,研究了地鐵車(chē)站深基坑穩(wěn)定性及其圍護(hù)體系變形規(guī)律。主要工作有:本文結(jié)合軟土地區(qū)特殊的水文地質(zhì)條件,對(duì)軟土場(chǎng)地基坑開(kāi)挖全過(guò)程的應(yīng)力及變形理論進(jìn)行了研究,重點(diǎn)探討了深基坑變形的機(jī)理及規(guī)律,分析了深基坑圍護(hù)結(jié)構(gòu)變形主要影響因素,并且對(duì)深基坑變形的時(shí)空效應(yīng)進(jìn)行了探討。結(jié)果表明,在基坑開(kāi)挖與圍護(hù)過(guò)程中,作用在開(kāi)挖面上的豎向卸荷與作用在圍護(hù)結(jié)構(gòu)擋土面水平方向卸荷使圍護(hù)結(jié)構(gòu)的受力和變形隨著時(shí)間與空間的變化而不斷變化,即時(shí)空效應(yīng)貫穿于深基坑開(kāi)挖的整個(gè)過(guò)程之中,且軟土場(chǎng)地基坑工程的時(shí)空效應(yīng)更加顯著。水文和工程地質(zhì)條件、周邊環(huán)境、支護(hù)體系的類(lèi)型、深基坑工程設(shè)計(jì)與施工的規(guī)模是影響基坑圍護(hù)結(jié)構(gòu)變形的主要因素�；诹合髽虻罔F車(chē)站的周邊環(huán)境和支護(hù)方案,制定了該基坑工程施工監(jiān)測(cè)方案,對(duì)基坑支護(hù)體系的受力和變形進(jìn)行了實(shí)時(shí)監(jiān)測(cè),并對(duì)實(shí)測(cè)數(shù)據(jù)所呈現(xiàn)的規(guī)律進(jìn)行了研究。對(duì)基坑施工過(guò)程中支護(hù)結(jié)構(gòu)的水平位移、支撐體系軸力變化以及基坑周邊地表沉降隨基坑開(kāi)挖深度和時(shí)間的變化規(guī)律進(jìn)行了研究。由監(jiān)測(cè)數(shù)據(jù)分析可知:支撐體系和支護(hù)結(jié)構(gòu)對(duì)控制基坑的變形具有至關(guān)重要的作用,圍護(hù)墻體的水平位移、周邊地表沉降均小于控制值。由于軟土場(chǎng)地的流變特性,基坑圍護(hù)結(jié)構(gòu)變形所呈現(xiàn)出來(lái)的時(shí)空效應(yīng)特別顯著。建立了數(shù)值分析模型對(duì)深基坑開(kāi)挖全過(guò)程進(jìn)行模擬,并且運(yùn)用FLAC3D軟件對(duì)圍護(hù)結(jié)構(gòu)受力和變形性狀進(jìn)行了全過(guò)程數(shù)值分析,探討了深基坑圍護(hù)結(jié)構(gòu)水平位移及地表沉降變化規(guī)律,現(xiàn)場(chǎng)監(jiān)測(cè)數(shù)據(jù)驗(yàn)證了數(shù)值模擬模型的合理性和可靠性。
[Abstract]:The economic development in the eastern coastal areas of China is rapid, and the demand for land resources is increasing with the rapid development of cities. However, limited land resources are becoming an important limiting factor for urban development. Therefore, the development and utilization of underground space is the mainstream trend of urban development, especially the construction of subway has become a hot direction of traffic development in major cities. The southeast coastal city of our country is a typical soft soil foundation. The engineering geological condition is complex, the construction is difficult and the construction safety hidden danger is great. Therefore, it is of great practical significance to study the deformation of deep foundation pit support structure of subway station in soft soil area. Based on the deep foundation pit engineering of Liangxi Bridge Metro Station on Wuxi Metro Line 2, this paper studies the stability of deep foundation pit and deformation law of its enclosure system by using the method of field monitoring and numerical analysis. The main works are as follows: combining with the special hydrogeological conditions in the soft soil area, the stress and deformation theory of the excavation of the soft soil site is studied, and the mechanism and law of the deformation of the deep foundation pit are emphatically discussed. The main factors influencing the deformation of deep foundation pit enclosure are analyzed, and the space-time effect of deep foundation pit deformation is discussed. The results show that in the excavation and retaining process of foundation pit, the vertical unloading acting on the excavating surface and the horizontal unloading acting on the retaining surface of the retaining structure make the stress and deformation of the retaining structure change with the change of time and space. That is, space-time effect runs through the whole process of deep foundation pit excavation, and the space-time effect of soft soil site foundation pit engineering is more significant. Hydrological and engineering geological conditions, surrounding environment, type of supporting system, design and construction scale of deep foundation pit are the main factors influencing deformation of retaining structure of foundation pit. Based on the surrounding environment and supporting scheme of the railway station of Liangxi Bridge, the construction monitoring scheme of the foundation pit is established, the force and deformation of the supporting system of the foundation pit are monitored in real time, and the regularity of the measured data is studied. In this paper, the horizontal displacement of supporting structure, the axial force change of bracing system and the variation of ground surface settlement around foundation pit with excavation depth and time during foundation pit construction are studied. From the analysis of the monitoring data, it can be seen that the bracing system and the supporting structure play an important role in controlling the deformation of the foundation pit, and the horizontal displacement of the retaining wall and the surface settlement around the wall are all less than the control value. Due to the rheological characteristics of soft soil site, the space-time effect of foundation pit enclosure deformation is particularly significant. The numerical analysis model is established to simulate the whole process of deep foundation pit excavation, and the stress and deformation characteristics of retaining structure are analyzed by FLAC3D software, and the horizontal displacement and ground subsidence of deep foundation pit enclosure are discussed. The field monitoring data verify the rationality and reliability of the numerical simulation model.
【學(xué)位授予單位】：湖南工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：TU753

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 張彬,王釗,彭亞明,張偉,馬天駿;土本構(gòu)模型研究的現(xiàn)狀及展望[J];桂林工學(xué)院學(xué)報(bào);2003年03期

2 劉金培;;SMW工法在基坑圍護(hù)中的應(yīng)用[J];河北交通科技;2009年02期

3 劉艷;;深基坑監(jiān)測(cè)技術(shù)及進(jìn)展[J];山西建筑;2007年32期

4 高德恒;王小剛;何振元;;混凝土支撐軸力監(jiān)測(cè)分析[J];人民珠江;2008年06期

5 寇曉東,周維垣,楊若瓊;三維快速拉格朗日法進(jìn)行小灣拱壩穩(wěn)定分析[J];水利學(xué)報(bào);2000年09期

6 劉寶琛;急待深入研究的地鐵建設(shè)中的巖土力學(xué)課題[J];鐵道建筑技術(shù);2000年03期

7 楊林德,鐘才根,曾進(jìn)倫;基坑支護(hù)位移和安全性監(jiān)測(cè)的動(dòng)態(tài)預(yù)報(bào)[J];土木工程學(xué)報(bào);1999年02期

8 俞建霖,龔曉南;基坑工程變形性狀研究[J];土木工程學(xué)報(bào);2002年04期

9 孫凱,許振剛,劉庭金,方宗新;深基坑的施工監(jiān)測(cè)及其數(shù)值模擬分析[J];巖石力學(xué)與工程學(xué)報(bào);2004年02期

10 沈珠江;結(jié)構(gòu)性粘土的彈塑性損傷模型[J];巖土工程學(xué)報(bào);1993年03期

相關(guān)博士學(xué)位論文 前1條

1 劉用海;寧波軟土工程特性及其本構(gòu)模型應(yīng)用研究[D];浙江大學(xué);2008年

，

本文編號(hào)：2422567