北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）设计

兰州交通大学毕业设计（论文）兰州交通大学毕业设计（论文）任务书课题北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）设计姓名宿稳平专业土木工程班级土木088班设计任务1．根据所给资料，根据工程地质与水文地质条件，参照区间隧道设计规范和标准，进行线路平纵断面设计、结构设计（包括主体结构设计、附属结构设计和临时结构设计。）并绘制区间隧道标准断面图、区间隧道标准断面配筋图、区间隧道纵断面图、区间隧道结构平面图、风道结构设计图。2.对区间隧道主体结构设计中结构型式及结构支护参数及尺寸进行计算、结构计算包括结构二维计算。对荷载与荷载组合进行计算。3.进行施工组织设计。施工单位的施工组织设计（实施性施工组织设计）应包括以下内容：隧道工程说明书，工地详细平面布置图，工程预计进度表，各工程项目分月完成工作量表，各项资源计算表及说明，组织机构设置，劳动力分月表，各项材料分月需要量表，施工机具需要量及使用起讫日期表，材料及备品需要量表，技术复杂工序及新施工方法的技术操作规定，保证质量及安全的技术组织措施等。4.编写设计说明书。应包括自然条件，工程概况，设计依据及各项技参数的选定和设计内容等5.分别用中英文撰写毕业设计摘要（500字左右），并用计算机打印。设计要求1．根据所给资料，参照《地铁设计规范》<GB50157-3003>和《地下铁道工程施工及验收规范》<GB50299-1999>,《混凝土结构设计规范》<GB50010-2002>，设计并用CAD制图软件绘制隧道纵横断面图（1：1000）。2．进行衬砌结构的设计和计算。参照标准图进行隧道衬砌结构设计，利用给定或自编的程序计算衬砌结构的内力并检算其抗压和抗拉强度。3．进行施工组织设计。4．编写设计说明书。5.编写英文的摘要。指导教师签字系主任签字主管院长签章兰州交通大学毕业设计(论文)开题报告表课题名称北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）设计课题来源工程实际课题类型AY导师学生姓名学号专业土木工程一、调研资料的准备北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）处的地质资料和地形图，《地铁设计规范》<GB50157-3003>和《地下铁道工程施工及验收规范》<GB50299-1999>,《混凝土结构设计规范》<GB50010-2002>，和部分外文书籍。毕业设计目的设北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道），其结构的设计使用年年限为100年，按荷载基本效应组合计算，衬砌结构的抗震作用符合8度抗震烈度，地下工程的主要部件的防火等级为一级。在战时应能满足人防工程的要求。三、思路与预期成果根据相关的规范《地铁隧道设计规范》和设计要求进行设计，并能够按期的完成毕业设计，基本掌握地铁隧道的设计。尤其对北京地区地铁隧道从设计到施工获得深入了解，为以后工作打下基础，得到实践经验。四、阶段任务的完成内容及时间安排第5周：查阅外文资料，并以其进行翻译和学习。第5-6周：熟悉图纸和相应的设计要求，仔细研究地质条件，明确基本的设计方向。第8周：确定开挖断面面积及结构断面形式。第9周：和同组同学进行沟通确定相邻断的衔接问题。第10-11周：衬砌结构设计及检算。第12周：绘制衬砌结构横断面图。第13周：整理以前的计算资料。第14周：熟悉隧道施工组织设计内容。第15周：施工方案的选择，组织机构设置和施工队伍的分工，并交开题报告。第16周：临时工程和总体工程进度安排，监控量测和施工控制测量。第17周：整理资料，准备答辩。（可另加附页）指导教师意见签名：年月日课题类型和性质：（1）A—工程设计；B—技术开发；C—软件工程；D—理论研究；（2）X—真实课题；Y—模拟课题；Z—虚拟课题（1）、（2）均要填，如AY、BX等。兰州交通大学毕业设计（论文）学生自查表（中期教学检查用）学生姓名专业土木工程班级指导教师姓名职称讲师课题名称北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）设计个人精力实际投入日平均工作时间6小时周平均工作时间42小时迄今缺席天数0出勤率%100%指导教师每周指导次数3次每周指导时间（小时）9小时备注毕业设计（论文）工作进度（完成）内容及比重已完成主要内容%待完成主要内容%任务计划书，开题报告；英文资料的翻译;地形平面图的绘制，地质剖面图，限界的确定;迂回风道结构图的绘制，区间隧道横断面图的绘制;隧道结构荷载的确定以及结构内力计算。55迂回风道衬砌的内力计算与检算；区间隧道衬砌的检算与配筋；施工组织方案的确定；整理以前的计算资料与图纸；并撰写设计说明书。45存在问题在进行结构内力计算时，运用软件sap2000不太熟练，甚至不足；由于对盾构法施工不太熟悉，在设计中有诸多不合理之处；由于区间隧道结构底板下有层间水，是否考虑抗浮验算存在问题；在施工组织中需多查阅资料，以完善和补充。指导教师签字：年月日摘要本毕业设计主要包括两个部分，第一部分是北京某区间（K13+510.000—K13+585.600）隧道结构设计；第二部分是北京某区间（K13+510.000—K13+585.600）隧道施工组织设计；在第一部分区间隧道结构设计中，根据工程地质与水文地质条件，参照区间隧道设计规范和标准，对区间隧道进行结构设计（包括主体结构设计、附属结构设计），并绘制区间隧道横断面图、区间隧道纵断面图、区间隧道结构平面图、风道结构设计图。通过施工方案的比选，确定盾构法施工，隧道衬砌结构平板型钢筋混泥土管片，利用fortran程序进行衬砌内力计算与检算，并对其进行相应的强度和抗浮验算。第二部分是区间隧道施工组织设计，根据隧道施工方法和隧道周边的环境情况，对施工前准备工作，施工场地布置，隧道开挖与衬砌结构施工等进行设计，并编制了工程进度计划，编写了相应的质量、安全、环境保护等措施。关键词：盾构；结构设计；内力计算；检算；施工组织 ABSTRACTThedesignmainlyincludestwoparts.Thefirstpartisthetunnelstructuredesignofarange(theK13510.000-theK13585.600);Thesecondpartisarange(theK13510.000-theK13585.600)tunnelconstructiondesign.Inthefirstpartofthesectiontunnelsstructuraldesign,engineeringgeologicalandhydrogeologicalconditions,thereferenceintervaltunneldesignnormsandstandards,structuraldesign(includingthemainstructureofthedesignoftherunningtunnels,subsidiarystructuraldesign),anddrawthecross-sectionaldiagramoftherunningtunnels,therangeoftunnellongitudinalsectionstructureplanofrunningtunnels,ductstructuredesign.Comparisonandselectionoftheconstructionprogramtodeterminetheshieldconstruction,thestructureofflatreinforcedconcretetunnelliningsegments,fortranprogramliningcalculationandCalculation,andthecorrespondingstrengthandanti-floatingchecking.

Thesecondpartisthetunnelsectionconstructionarrangementdesign.Accordingtothetunnelconstructionmethodsandtheenvironmentaround,thepreparationbeforetheconstruction,constructionsitelayout,tunnelexcavationandliningconstructionisdesigned.Theprojectschedule,thequality,thesafetyandtheenvironmentprotectionaremade.Keywords:shield;structuraldesign;internalforcecalculation;checkingcalculation;constructionorganizations兰州交通大学毕业设计（论文）1目录1. 绪论 ⑤建立规范统一的测量记录手薄，认真填写测量记录。6.8.3消防安全措施（1）消防器材的放置。场地上重要的机械设备、油库、办公室、更衣室、仓库等均设置消防器材。（2）站台层和站厅在显眼处也设置消防器材。隧道内每隔50m设置一个灭火器，盾构头部设置一组灭火器。（3）隧道内严禁吸烟。在井下合理位置布置一吸烟点，并配备灭火器材。结论本次设计中主要是北京某地铁线区间（K13+510.000-K13+585.600）隧道（含区间迂回风道）设计。包括区间隧道和迂回风道的平纵断面设计、衬砌内力的计算与检算以及施工组织设计两部分内容。（1）在结构设计过程中，综合地质情况、施工方法、以及车辆类型（A型车）决定隧道限界，断面形式，最终确定区间隧道为圆形结构，迂回风道为直墙圆拱结构形式。（2）在计算结构衬砌内力的计算与检算过程中，运用fortran程序和Excel计算，通过检算，管片能够满足强度要求。（3）对结构进行抗浮验算，能够满足要求，并进行了管片断面设计。（4）在施工组织设计中，全面考虑施工高效、科学、安全的原则，结合盾构施工的特点，详细的进行设计，能够满足施工要求。（5）同时在断面设计中用CAD绘制区间隧道的平面图、纵断面图、迂回风道横断面图。在设计过程中，大量地用运了EXCEL、Word、AutoCAD等软件。同时，设计严格依据《地铁设计规范》和其他规范进行。致谢毕业设计是对大学四年的的学业成果的一次检阅，同时又是从面向社会、面向基层、面向工程出发，其目的是使学生在学完培养计划所规定的基础课、技术专业课及各类必修和选修专业课之后，通过这次毕业设计，在培养学生从事科技工作正确思想方法的同时，培养学生勇于探索、敢于创新、实事求是、用实践来检验理论，全方位地考虑问题等科学技术人员应具有的素质。通过设计，我深刻地感受到理论知识与工程实践相结合的重要性，从设计中，我全面地锻炼了自己综合运用知识以及捕捉信息的能力，而且我也深深地发现自己在学习过程中的欠缺和不足，基础知识不够扎实。完成这次毕业设计后，我对今后工作和学习充满信心，对未来充满必胜的信念！经过了近三个月的努力，毕业设计终于完成了。随着大学四年最后一项学习任务的完成，也标志着我在大学的学习、生活将告以段落。四年以来，老师的悉心教导、同学的热情帮助，让我学到了许多知识，同时也让我学会了做人的道理，这将是我一生最大的财富。而本次毕业设计是对我大学四年学习成果的一次综合检验，也是对我四年所学的专业知识的进一步强化和提高。在该设计的构思、设计以及定稿过程中，我得到了陈志敏老师耐心、细致的指导。陈老师虽然教学任务和工程任务都比较重，但是他总是尽他所能的帮助我们，并为我们提供必要的参考资料以及很多的经验指导。由于我们所学的知识与完成设计所需要的知识存在一定断层，陈老师不辞辛劳的为我们补课。在此，我对陈老师的悉心教导表示诚挚的感谢！此外，在做设计的过程中，我的同学也给予了我很多帮助，在此也表示感谢。宿稳平2012年6月7日参考文献[1]张一宁.地铁旁通道和冻结法施工风险分析与建议[J].城市道桥与防洪，2010[2]刘志强.隧道工程[M].徐州：中国矿业大学出版社，2002[3]高少强.隋修志.隧道工程[M].北京：中国铁道出版社，2003[4]朱合华.地下建筑结构[M].北京：中国建筑工业出版社，2005[5]夏军武.贾福萍.结构设计原理[M].徐州：中国矿业大学出版社，2007[6]翁家杰.地下工程[M].北京：煤炭工业出版社，1995[7]秦汉礼.盾构隧道钢筋混凝土管片制作技术[J].隧道建设，2006[8]朱合华.土压平衡盾构法施工参数的模型试验研究[J].岩土工程学报杂志编辑部，2006[9]翁家杰.地下工程[M].北京：煤炭工业出版社，1995[10]孙均.地铁隧道盾构掘进施工市区的环境土工安全技术标准及其变形与沉降控制[J].世界隧道，2000（增刊）：233~240[11]施仲衡.张弥等.地下铁道设计与施工[M].西安：陕西科学技术出版社，1997.6，378~381附录一翻译部分原文AnalysisofSettlementCausedbyTBMConstructioninSandFormationsinBeijingABSTRACTBasedondatacollectedintunnelboringmachine(TBM)constructioninBeijingsubway,soilsettlementpredictionmodelsforsandformationsareanalyzedandverified.ThroughtheanalysisofPeck’sformula,thepaperpointsoutthatthepreconditionistodeterminethecoefficientofsettlementgroovewidth(i),whileiisfurthercontrolledbythemaximumsettlementofsingletunnel(δ1max).ByusingthesettlementequationofTakeyamaTakashi,δ1maxcanbecalculateddirectly,buttheelasticmodulus(E)shouldbeanequivalentvaluethatrepresentsallthesoilsinvolved.Inthecalculationofthecoefficientofsettlementgroovewidth(i)byusingO＇Reilly-Newmethod,theresultsislargelyaffectedbytheformationparameters.InordertofindanidealmodeltopredictthesettlementinTBMconstructioninBeijingsandyformation,modifiedcalculationmethodsofEandiarerecommended.Theresultsshowthatthemaximumsettlementinthegroundsurface,thetotalwidthofsettlementgrooveandthesettlementcurveinthecrosssectionmatchmonitoreddataverywell.Fordoubleparalleltunnels,thesettlementatanypointcanbecalculatedbyaddingindividualsettlementgeneratedbyeachtunnelconstruction,andeachofwhichcanbecalculatedbyusingtheformulasofPeckandTakeyamaTakashi.Butthesettlementsatthecenterlineofeachtunnelaredifferent.Theamountofsettlementisaffectedbyconstructionsequenceofthetwotunnels.Theearlierthetunnelisconstructed,thelargertheeventuallysettlementis.KEYWORDSTBM;Settlement;CoefficientofSettlementGrooveWidth;Peck;TakeyamaTakashi;BeijingsubwayINTRODUCTIONRecentyearstheBeijingsubwayextendsatthespeedofabout100kmeveryyear.MostofthesubwaytunnelsareconstructedbyusingearthpressurebalanceTBMmethod.BecauseBeijingcityliesintheintersectionareaofplainandmountain,themainformationsencounteredinTBMconstructionaresand,gravel,siltysand,finesand,clay,etc.EspeciallyineasternBeijing,thesubwaytunnelsarenormallyinthedepthof20munderground,andthesand-gravelformationsarefullofwater.Inthiskindofsituation,settlementcontrolisabasicrequirement;otherwisebuildings,pipelinesandotherundergroundinfrastructureswillbeaffectedseverely,evendamaged.SohowtoexactlypredictsoillossinTBMconstructionisveryimportant.ByfarthemethodsforanalysisofsettlementinducedbyTBMarederivedfromtheoretical,experienceornumericalanalysis.Amongthem,Peck’sformulaiswidelyaccepted.Itsupposesthesettlementiscausedbysoillossandthevolumeofsettlementgrooveequivalentstothevolumeofsoillossifconstructionisunderundrainedconditions.ThecurveofgroundsettlementgroovebyPeck’sformulaisdistributedintheshapeofnormalcurve(Peck,1969).O＇Reilly-NewputforwardanotherformulatocalculatethesettlementgroovewidthgeneratedbytheTBMconstructionindifferentburieddepthoftunnels(O'Reilly,1982).Attewellinducedothertwofactors,kandn,tocalculatethesettlementgroovewidth(Attewell,1986).In1982FujitaofJapananalyzed74settlementcasescausedbyTBMconstruction.TheresultshowedthattheshapeofthesettlementgroovewasverysimilartothatofPeck’scurve.Thereafter,theJapanesescholarTakeyamaTakashiabsorbedthelatestresearchresultsfromelasticfiniteanalysis,analyzedthemonitoreddata,andthenbroughtforwardthemodifiedsettlementpredictionformula(Rankin,1988andWei,2010).Anyway,ifthesettlementistobepredictedproperly,besidesemployingasuitablesettlementformula,thechoiceoftheproperparametersofsoilsandconstructionisequallyimportant.Thefollowingpartdemonstratessomesuccessfulpredictionpracticefortheselectionofsettlementcalculationformulaanddisposingtechniqueofsoilparameters.SETTLEMENTDETERMINATIONTHEORIESPeck’sformula.ThemostacceptedPeck’sformulaforthecalculationofgroundsettlementyieldedbytunnelboringconstructionisasfollows:So,Equation(1)takestheformDeterminationofcoefficientofsettlementgroovewidth(i).Therearethreewaystoobtainthecoefficientofsettlementgroovewidth(i).Method1.AccordingtotherecommendationofEnglishscholarO＇Reilly-New,icanbedeterminedaccordingtotunneldepthandsoiltypes,asshowninEquation(4).i=α·Z(4)Whereα=Factorrelatedtosoil.α=0.4forhardclay;α=0.7forsoftclay;α=0.5formediumhardclay;α=0.2~0.3forsand.Z=Tunneldepthfromgroundsurfacetothetopofatunnel,m.Method2.AccordingtoKloofandSchmid(Zhouwenbo,2004;Yinluchao,1999;ZhangFengxiang,2005),forplasticundrainedclay,thecoefficientofsettlementgroovewidthcanbecalculatedbyEquation(5).WhereR=Outerdiameteroftunnelbore,mMethod3.icanbecalculatedaccordingtogeologicalcondition,tunneldepthandtunnelradius,asshowninEquation(6).Whereφ=Internalfrictionangelofsoil,degreeFurthermore,scholarCordingregardssettlementgrooveasVshapeslot,sothesettlementgroovewidthcanbesimplifiedas:B=5i(7)WhereB=Settlementgroovewidth,mExperienceformulaofTakeyamaTakashi.Throughthestudyofmonitoreddataandtheachievementofelasticfinite,TakeyamaTakashideducedthefollowingequationtocalculatethemaximumsettlementgeneratedbytunnelTBMconstruction.Themaximumsettlementproducedbysingletunnelconstructionis:Themaximumsettlementinducedbydoubletunnelsconstructionis:Whereδ1max=MaximumsettlementinsingletunnelTBMconstruction,mδmax=MaximumsettlementindoubletunnelTBMconstruction,mH=Distancebetweenthetopoftunnelandgroundsurface,mD=Outerdiameteroftunnelbore,mE=Weightedmeanvalueofsoilelasticmodulus,MPaW=Netdistancebetweentwotunnels,mCASESTUDIES:TBMCONSTRUCTIONBETWEENSTATIONSOFSANYUANBRIDGEANDLIANGMARIVERINBEIJINGSUBWAYLINE10ThetunnelbetweenstationsofSanYanBridgeandLiangMaRiverinBeijingSubwayLine10isconstructedbyearthpressurebalancetunnelboringmachine.Thedistancebetweenlefttunnelandrighttunnelis12m.Thedepthbetweenthetopoftunnelandgroundsurfaceis12~16m,theouterdiameteroftunnelboreis6.28m.Theformationsencounteredintheconstructionaresilt,siltyclay,clay,siltysand,andsand.Thegroundwaterisabovethebottomoftunnelbase(Co.,Ltd.2003).Whilethetunnelsectionisrunningalongtheeastthirdringroad,therearemanybridges,buildings,pipelinesabovethetunnel,sothesettlementcontroloftheconstructionisverystrict.InordertodiscussthesettlementpredictiontheoryforBeijingsubwayconstruction,asanexample,onerandomsectionischosen,forsimplicity,hereandthereafternameitSectionA.Itslengthis50m,thedistancebetweendoubletunnelscenterlinesis12m,andthecoverdepthoftunnelHis14.2m.Thetunnelisadvancedintheformationsoffinesandandmediumcoarsesand.ThemainparametersofsoilsarelistedinTable1.SOILSETTLEMENTPREDICTIONMaximumgroundsurfacesettlementcausedbysingletunnelTBMconstruction.ByusingEquation(9),themaximumgroundsurfacesettlementcausedbysingletunnelTBMconstructioninSectionAcanbecalculated.HereH=14.2m,D=6.28m,whileEisregardedasweightedaveragevalueofeachsoillayers,asshowninEquation(10).WhereEs=Weightedcompressionmodulusofallsoillayers,MPaEsi=Compressionmodulusofsoillayeri,MPahi=Depthofsoillayeri,mByusingEquation(10)andthedatainTable1,Es=15.2676MPa.Moreover,theelasticmoduluscanbeobtainedbyusingEquation(11)ifcompressionmodulusisknown.Coefficientofsettlementgroovewidth(i)andsettlementgroovewidth(B).Inthisproject,theformationsencounteredintunnelconstructionaresaturated,dense,lowcompressiblesiltysandandmediumcoarsesand.Whiletheformationsabovethetunnelareplasticmediumcompressiblesiltyclayanddensemediumcompressiblesilt.Asmentionedbefore,forsandlayersi=0.25Z;forsiltyclayi=0.5Z;forsilti=0.35Z.Soheretheweightedmeanvalueisdefinedasthefinalivalue,asshowninequation(12).=Accordingtoequation(7),thetotalsettlementgroovewidthcausedbysingletunnelboringconstructionis5i=5×6.788m=33.942m.Groundsurfacesettlementcausedbysingletunnelconstruction.Ifiandδ1maxareknown,thegroundsurfacesettlementinanypoint(δ1(x))canbecalculatedbyequation(3),asshowninTable2.Notethatδ1max=14.1mminthetable.Table2indicatesthatifthedistancefromanypointingroundsurfacetohorizontaltunnelcenterlineisgreatthan17.5m,thenthesettlementislessthan0.5mm.Thismeansatthatpointtherewillonlytinyinfluencebytunnelboringconstruction.Sothetotalsettlementgroovewidthcanbeconsideredas2×17.5=35m,whichismuchclosertothevalueof5i(33.94m).Groundsurfacesettlementcausedbydoubletunnelsconstruction.Maximumsettlementafterdoubletunnelsconstruction.Generallythenearerdistancethedoubletunnelsis,thegreateradditionalsettlementcausedbythetunnelboringconstructionis.Intheprojectmentionedabove,δ1max=14.1mm,thenetdistancebetweenthetwotunnelsW=5.72m,tunneldiameterD=6.28m.Thusfromequation(9)δmax=17.6mm,thatmeans,themaximumgroundsettlementafterthedoubletunnelsconstructionis17.6mm.Settlementdevelopingprocessintheconstructionofthesecondtunnel.Followingistheanalysisofsettlingprocessintheconstructionperiodofthesecondtunnel.(1)Intheperiodofthefirsttunnelhasbeenfinishedandthesecondtunnelconstructionnotyetbegin,themaximumgroundsettlementcausedbythefirsttunnelisδ1max=14.1mm,asmentionedabove.Withtheincreaseofthedistancetotunnelcenterline,thegroundsettlementcausedbythefirsttunnelconstructionwillgraduallydecrease.Byusingequation(3)andsettingi=6.788m,wecanobtainδ1(6)=9.6mmwhenx=6mandδ1(12)=3.0mmwhenx=12mrespectively.(2)Theadditionalgroundsettlementcausedbythesecondtunnelconstructionisthesubtractionofthetotalmaximumsettlementcausedbydoubletunnelsconstructionfromthesettlementcausedbythefirsttunnelconstruction.(LiuBo,TaoLong-guangandDingCheng-gang,etal.2006).Forthepointsonsymmetrytunnelliner,x=6m,δ2(6)=δmax-δ1(6)=17.6-9.6=8.0mm.(3)Theaccumulatedgroundsettlementabovethesecondtunnelcenterlineconsistsoftwoparts.Thefirstpartisthesettlementcausedbythefirsttunnelconstructioninthepoint,δ1(12)=3.0mm.TheSecondpartisthesettlementcausedbythesecondtunnelconstruction,whichcanbecalculatedbyusingequation(3).Hereδ2(6)=8.0mm,i=6.788mm,δ2max=11.8mm.Sothetotalgroundsettlementabovethesecondtunnelcenterlineis:δ2max+δ1(12)=11.8+3.0=14.8mm.(4)Theaccumulatedgroundsettlementabovethefirsttunnelcenterlinealsoconsistsoftwoparts.Firstthesettlementcausedbythefirsttunnelconstructioninthepointδ1max=14.1mm.Thesecondpartisthesettlementcausedbythesecondtunnelconstruction,whichcanbecalculatedbyusingequation(3),whereδ2(12)=2.51mm,i=6.788mm.Sothetotalgroundsettlementabovethefirsttunnelcenterlineis:δ1max+δ2(12)=14.1+2.51=16.61mm.Throughtheaboveanalysis,thetotalsettlementabovethesecondtunnelcenterline(14.8mm)islessthanthatabovethefirsttunnelcenterline(16.61mm).Totalsettlementatanypointafterdoubletunnelscompletion.Thesettlementatanypointingroundsurfacecausedbytwodoubletunnelsconstructioncanbecalculatedbyfollowingequation:δ(x,y)=δ1(x)+δ2(y)(13)Wherex=Horizontaldistancefromcalculatingpointtocenterlineoffirsttunnely=HorizontaldistancefromcalculatingpointtocenterlineofsecondtunnelInsectionA,thelefttunnelisfirstlyconstructed,thentherighttunnel.Afterthetwotunnelscompletion,thesettlementatanypointingroundsurfacecanbecalculated:(1)Ifcalculatingpointislocatedattheleftofthelefttunnel,thenxequalsthedistancefromthepointtocenterlineoflefttunnel,andy=W+D+x.Forinstance,ifx=6m,theny=18m,δ(6,18)=δ1(6)+δ2(18)=9.6+0.3=9.9mm.(2)Ifcalculatingpointliesinthemiddleofthecenterlinesoflefttunnelandrighttunnel,forexample,ifx=6m,theny=W+D-x=6m,δ(6,6)=δ1(6)+δ2(6)=9.6+8.0=17.6mm.Thisvaluerepresentsthegreatestsettlementcausedbydoubletunnelsconstruction,wherelocatedinthegroundabovethenearesttunnelliner.(3)Ifcalculatingpointisattherightoftherighttunnel,e.g.,ify=6m,thenx=18m,δ(18,6)=δ1(18)+δ2(6)=0.4+8.0=8.4mm.Furthermore,theindividualandaccumulatedgroundsettlementcausedbythefirstandthesecondtunnelsarecalculated,asshowninFigure1.COMPARISONOFPREDICTEDSETTLEMENTANDMONITOREDDATAMonitoredgroundsettlementgeneratedbythefirsttunnelconstruction.Inordertoevaluatethesettlementinducedbythefirsttunnelconstruction,elevensettlementobservationpointsingroundsurfaceoflefttunnelcenterlineareburiedinSectionAinthelengthof50m.Thedistancebetweentwoneighboringobservationpointsis5m,andthepointsareenumerated1~11.ThelefttunnelwasfirstlyconstructedandpassedthroughsectionA,then6monthslater,therighttunneldrilledthroughsectionAalso.Table3listedtheobservedsettlementdataafter60daysoflefttunnelpassedthrough,whilerighttunnelnotreachedhereyet(about150mawayfromsectionA).Theaveragesettlementofthe11observationpointsingroundsurfaceabovethelefttunnelcenterlineis13.56mm,whilethemeansettlementofthe7observationpointsingroundsurfaceabovetherighttunnelcenterlineis4.88mm.Thesesettlementsarecausedonlybytheconstructionoflefttunnelandobservedafter60dayslateroftheconstruction.Figure2comparedthetheoreticalsettlementvalueandactuallyobservedsettlementingroundsurfaceabovethelefttunnelcenterline.Itcanbeseenthatthetheoreticalvalue(δ1max=14.1mm)almostequalstheaveragesettlementof11observationpoints.Figure3showsthecomparisonofobservedsettlementvalue,whichismonitoredafter60dayslateroftheconstructionoflefttunnel,andthecalculatedsettlementingroundsurfaceabovetherighttunnelcenterline.Itcanbeseenthatalthoughthereare12mbetweenlefttunnelcenterlineandtherighttunnelcenterline,yetproducedabout4.0mmsettlementontherighttunnelcenterlineonlybecauseoftheconstructionoflefttunnel.Undertheconditionofδ1max=14.1mm,asmentionedearlier,δ1(12)=3.0mm.Sothedeviationbetweenobservedvalueandtheoreticalvalueisabout1mm,whichdemonstratesabovetheoreticalformulaisbelievable.Accumulatedsettlementsbydoubletunnelsconstruction.Figure4showsthegroundsettlementatobservationpointnumber10.Afterthelefttunneladvancedhereandreachedstable,theultimatesettlementwas12.75mm.Aftertherighttunnelpassedthrough,theadditionalsettlementincreasedforaperiod,eventuallystabilizedat4.46mm,atthattimethetotalsettlementatpoint10reached17.21mm,whichwasveryclosetothetheoreticalvalue16.61mmFigure5showsthemonitoreddataofarandompointSYA24,whichislocatedattherightoftherighttunnel.Thedistanceofthepointtothelefttunnelcenterlineis18.5m,totherighttunnelcenterlineis6.5m.Lefttunnelconstructioncaused1.85mmsettlement,thenwhentherighttunnelalsofinisheditcausedtotal7.61mmsettlementatthatpoint.Whenthelefttunnelpassedthrough,thesettlementofthepointx=18.5isδ1(18.5)=0.3mm;whentherighttunnelpassedthrough,thesettlementofthepointy=6.5isδ2(6.5)=7.5mm.Accordingtoequation(13),thetotalsettlementatthepointshouldbe7.8mm,whichisveryclosertothemonitoredvalue7.61mm.Moreover,throughtheanalysisofallmonitoreddatagatheredinleftandrighttunnelconstruction,itisshowedthatthemaximumsettlementpointsaredistributedintheareasbetweenlefttunnelandrighttunnel,andmostofthemarelocatedatthegroundsurfaceabovethenearesttunnelliner,thevalueisinthescopeof17mmand20mm.Comparedwiththetheoreticalvalueδmax=17.6mm,thedeviationisacceptable.Thereforethecalculationequationsmentionedabovefortotalsettlementindoubletunnelconstructionisbelievable.Maximumgroundsettlementsunderdifferentdistancebetweentwotunnels.Forδmaxmustgreatthanδ1max,equation(9)isonlysuitableundertheconditionofW/(2D)<0.7inthecalculationofsettlementcausedbydoubletunnelsconstruction.Therefore,formosttunnelsinBeijingsubway,whilethediameteroftunnelis6m,thedistancebetweentunnelcenterlinesshouldbettergreatthan14m,sothatthetotalsettlementinthefirsttunnelcenterlinewillhaveonlytinyincreasebecauseoftheconstructionofthesecondtunnel.Figure6showsthattotalsettlementalmostkeeplinearincreasewiththedecreaseofthenetdistancebetweentwotunnels,ifthenetdistanceislessthan1.4D.Monitoredsettlementgroovewidth.Inordertodeducethesettlementgroovewidth,theobservationdatafromthecrosssectionaroundpointnumber6areutilized.Theobservationpointsareinline,whichthelinedirectionisperpendiculartothedirectionoftunnelcenterline.Total7monitoringpointsaresetuponbothsideofpointNo.6,twoofthemsetintheleft,andtheothersareintheright.Thedistanceofnearbytwomonitoringpointsis3m.Thedatarecordedarelistedintable4andplottedonFigure7.Itcanbeseenthatthecalculatedvaluecoincidesperfectlywiththeactualmonitoredsettlement.ThetotaltrendisalsoaccordwiththecurveofPeck’snormalsettlementcurveverywell.Themonitoredsettlementofthemostoutsidepointis1.82mm,whilethedistanceofthepointtothecenterlineofmaximumsettlementis15m.AlsoFigure5showedthattheactualmonitoredsettlementaroundobservationpointSYA24is1.85mm,whilethedistanceofthepointtothemaximumsettlementlineis18.5m.Thereforetheminimumsettlementgroovewidthcausedbysingletunnelconstructionisatleast30m.Accordingtothistrend,thewidthisdeducedtobe35m,whichisveryclosetotheabovecalculatedvalue33.941m.Sotheequationsforcalculatingthesettlementgroovewidthinthearticlearecorrect,andtheyaresuitableforpredictionthesettlementgeneratedinTBMtunnelconstructioninsandformationsinBeijingsubway.CONCLUSIONUpontheaboveanalysis,thefollowingconclusioncanbedrawn:(1)Ifsoilparametersareselectedproperly,thesettlementgeneratedbyTBMtunnelconstructioninBeijingsubwayinsandyformationscanbepredictedaccuratelybyusingtheformulasofPeckandTakeyamaTakashi.(2)WhensettlementiscalculatedwiththeformulaofTakeyamaTakashi,themaximumsettlementwillincreasewiththedecreaseofweightedelasticmodulus,andthesoilmodulusshouldcalculatedwiththeweightedaveragevalueofallsoillayers’compressionmodulus.(3)Thecoefficientofsettlementgroovewidth(i)shouldbetakenastheweightedaveragevalueofdifferentsoils.Thewidthofsettlementgroovecausedbysingletunnelconstructionisabout5i.(4)Themaximumsettlementforthedoubletunnelconstructionliesintheareasbetweentwotunnelcenterlinesifthenetdistancebetweenthemislessthan1.4tunneldiameter(D).Theinfluencebythefollowingconstructedtunnelwillbeminimizedifthenetdistancegreaterthan1.4D.(5)Thesettlementfromthemiddlelineofthetwotunnelcenterlinestooutsideisnotsymmetric.Groundsettlementnearthefirstlyconstructedtunnelwilllargerthanthatoflaterconstructedone.翻译对北京地区沙地层TBM隧道施工所造成沉降的分析摘要根据在北京地铁运用TBM开挖隧道施工过程中所得资料，利用土沉降预测模型对沙性土进行了分析和检验，通过Peck法则的分析，报告指出首要必须确定沉降槽宽度的系数（i）,而i值是进一步控制最大计算单隧道(δ1max)。通过TakeyamaTiakash方程，δ1max能够被直接计算出来，但是弹性模量E应该是一个代表各种土质的等效值，用O＇Reilly-New方法计算沉降槽宽度系数（i），其结果受土壤构造物参数大量的影响，为了找到一种理想的模型去预测北京地区沙性土TBM隧道施工带来的沉降，修正计算方法中的E和i值都是推荐值，其结果显示了地表沉降的最大值，整个沉降槽的宽度和沉降曲线与监测数据相符。对于平行双线隧道，其沉降在一定程度上能够通过增加对每个单线隧道施工引起的沉降的计算而算的，而单线隧道沉降由Peck和TakeyamaTakashi.法则计算，但是每条隧道的中心线沉降不同，沉降数量受两条隧道施工次序的影响，越早施工的隧道，其最终沉降量越大。关键词：TBM沉降沉降槽宽度PeckTakeyamaTakashi北京地铁说明近些年来，北京地铁以大约每年100公里的速度延伸着，大多数地铁隧道都利用TBM土压力平衡方法施工的，因为北京市位