《嵌入式技术》

地铁施工与地下水渗流的环境效应分析及应用学号：20130101姓名：张三三班级名称：土1304-1院系名称：土木工程学院2014年12月《嵌入式技术》结业报告摘要摘要以北京地铁王府井站西南风道为工程背景，针对松散含水地层工程地质及水文地质差、紧邻建筑物、地表环境要求严、施工条件恶劣、降水条件受到限制、大断面浅埋暗挖洞室稳定性差等不利因素，深入分析了地铁施工与地下水渗流的环境效应机理。利用地下工程中最先进的3D-σ三维有限元软件，采用增量变弹性与增量叠代的混合法，模拟计算了软弱围岩地铁的施工作业流程，考虑围岩介质的复杂性态、施工作业方式(包括分步开挖步序、支护结构形式和施工时机)和开挖面推进过程中的空间效应。得出了各步序拱顶下沉、收敛、地表沉降与开挖步的关系曲线。从达西定律出发，利用地下水动力学稳定流理论，针对实际工程，推导出了任意排列的承压—潜水井群降水计算过程，自行编制了Fortran程序，完成了处于潜水含水层和承压含水层群井降水的三维渗流分析及计算，形象地绘制了降水曲面。并利用3D-flow计算软件进行了降水曲线和流速的计算，与自行编制的程序进行了比较。最后计算了因水位变化引起的地面沉降最终值及随时间的变化曲线。首次将坑道涌水研究用于地铁，并对地铁坑道涌水的危害程度作出了合理预测和分析。根据坑道所处的不同含水层、以及坑道所处地层中的位置不同，自行推导了处于潜水含水层和承压含水层的，完整型和不完整型坑道稳定涌水量和水位降深的计算公式。根据不同的坑道涌水量、不同的水文地质情况对坑道开挖后可能的涌水引起的地面变形做出预测和分析。最后结合实例进行了验证、预测和分析，为行业人士对地铁涌水的处理和认识提供了参考和借鉴。关键词：环境效应；施工力学分析；地下水动力学；涌水；地面沉降AbstractAbstractBasedonthesouthwestairoutletofWangfujingstationinBeijingmetro,aimingatdisadvantagefactorssuchasbadconstructiongeologyandbadgeohydrologyinlooseaquiferousground,adjacenttobuildings,strictrequirementforgroundenvironment,poorconstructioncondition,limitedwaterloweringcondition,poorstabilityoflargesectionwithundergroundexcavationundershallowdepth,analyzeenvironment-effectmechanismofmetroconstructionandgroundwater-seepagethoroughly.Usethemostdeveloped3D-σthree-dimensionFEMsoftwareinundergroundproject,adoptcompoundmethodwithincrementvariableelasticityandincrementiteration,simulateandcalculateconstructionprocessofweaksurroundingrocksinmetro,considercomplicateproperties,constructionmethod(includeprocessofbystepexcavation,styleofsupportingstructureandconstructionopportunity)andspaceeffectinfaceexcavationprocess.Relationcurveofvaultsinkage,constringency,groundsubsideandexcavationstepineachprocessaregained.Researchongushingwaterintunnelisappliedtometroforthefirsttimeanddangerousdegreeofgushingwaterinsubwayispredictedandanalyzedreasonably.Accordingtovariouswatercontaininglayerandstratumtunnellocatedin,calculationformulaonstablegushingwaterquantityinsurfacewaterlayertunnel,pressurewaterlayertunnel,fullorfragmentarytunnelarededuced.Accordingtogushingwaterquantityandhydrologygeologyinvarioustunnel,grounddeformationcausedbygushingwaterintunnelispredictedandanalyzed.Atlast,verification,predictionandanalysisaremadewithexample,referenceisofferedtopeopleinthesameoccupationonpredictionandcognitionofgushingwaterinmetro.Keywords:environment-effect,Constructionmechanicsanalysis,groundwaterdynamics,flowing,groundsubside目录-I-目录第一章绪论.........................................................................................................11.1引言................................................................................................................11.2地铁施工与地下水渗流的环境效应危害分析............................................11.2.1地层开挖的环境效应危害分析.............................................................21.2.2人工降水的环境效应危害分析.............................................................21.2.3地下水向地铁坑道涌水的环境效应危害分析.....................................31.3国内外发展动态............................................................................................41.3.1岩土工程和环境岩土工程的国内外现状.............................................41.3.2地下工程力学分析国内外现状.............................................................51.3.3地下水位计算的国内外现状.................................................................81.3.4地面沉降研究现状.................................................................................81.3.5坑道涌水量研究现状...........................................................................101.4论文研究内容及创新点..............................................................................101.4.1主要研究内容.......................................................................................111.4.2主要创新点...........................................................................................111.4.3论文的不足之处及今后的研究方向...................................................12第二章工程背景...................................................................................................132.1工程概况......................................................................................................132.2工程特点......................................................................................................172.3施工方法......................................................................................................17第三章地铁施工效应分析...................................................................................203.1模拟依据和基础..........................................................................................203.1.1洞室开挖问题的空间模拟...................................................................203.1.2洞室开挖问题的计算模型...................................................................213.1.3材料、结构模拟及强度准则...............................................................223.1.4非线性问题的数值解法.......................................................................223.1.5围岩与支护的物理力学指标...............................................................23目录-II-3.1.6计算模拟的施工方案...........................................................................233.2计算模拟结果....................................