任务精读：分部开挖法（双语）课件讲解

隧道施工技术TunnelConstructionTechnologyPartialExcavationMethod分部开挖法分部开挖法目录TableofContentsPartialExcavationMethod分部开挖法的概念和分类1ConceptandClassificationofPartialExcavationMethod环形开挖预留核心土法2RingCutMethodwithCoreSoilReserved单侧壁双侧壁导坑法3SingleSideandDoubleSideHeadingMethod中洞法4MiddleHoleMethod课程小结5Summary分部开挖法的概念和分类ConceptandClassificationofPartialExcavationMethod01分部开挖法PartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved单侧壁、双侧壁导坑法SingleSideandDoubleSideHeadingMethod中洞法MiddleHoleMethodCD法、CRD法CDmethod,CRDmethod分部开挖法是把设计的巷（隧）道断面划分成若干部分，进行二次及其以上开挖，最后达到巷（隧）道设计开挖断面的一种施工方法。Partialexcavationmethodisamethodtodividethedesignedroadway(tunnel)sectionintoseveralpartstocarryoutthesecondaryandaboveexcavation,andfinally,reachthedesignexcavationsectionoftheroadway(tunnel).分部开挖法PartialExcavationMethod分部开挖法的概念和分类ConceptandClassificationofPartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved02环形开挖预留核心土法一般将断面分成为环形拱部、上部核心土、下部台阶三部分。Theringcutmethodwithcoresoilreservedgenerallydividesthesectionintothreeparts:ringarch,uppercoresoilandlowerbench.环形开挖预留核心土法RingCutMethodwithCoreSoilReserved1——上部弧形导坑开挖1–Excavationofupperarchheading2——上部左侧导坑开挖2–Excavationofupperleftheading3——上部右侧导坑开挖3–Excavationofupperrightheading4——上部核心土开挖4–Excavationofuppercoresoil5——下部开挖5–Lowerexcavation分部开挖法PartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved环形开挖预留核心土法优点Advantages在环形开挖预留核心土法中，因为上部留有核心土支撑着开挖面，而且能迅速、及时地建造拱部初期支护，所以开挖的工作面稳定性好。核心土和下部开挖都是在拱部初期支护保护下进行的，施工安全性好。台阶长度相对较长，以减少上、下台阶施工的干扰；同时该方法施工机械化程度较高，施工速度较快。Intheringcutmethodwithcoresoilreserved,thestabilityoftheexcavatedworkingfaceisgoodbecausethecoresoilisreservedintheupperparttosupporttheexcavationfaceandtheprimarysupportofthearchcanbeconstructedquicklyandtimely.Thecoresoilandtheexcavationofthelowerpartarebothcarriedoutundertheprimarysupportprotectionofthearch,andtheconstructionissafe.Thebenchisrelativelylongtoreducetheinterferenceofupperandlowerbenchconstruction.Meanwhile,themechanizationdegreeofconstructionwiththemethodishighandtheconstructionspeedisfast.特点及适用条件CharacteristicsandApplicableConditions分部开挖法PartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved环形开挖预留核心土法缺点Disadvantages虽然核心土增强了开挖面的稳定，但是，开挖过程中围岩要经受多次扰动，而且断面分块多，支护结构形成全断面封闭的时间长，这些都有可能使围岩变形增大。因此，它常需要结合辅助施工措施对开挖工作面及其前方岩体进行预支护或预加固。Althoughthecoresoilenhancesthestabilityoftheexcavationface,thesurroundingrockwillsuffermultipledisturbancesduringexcavation,thesectionisdividedintomultipleparts,andthesupportstructuretakesalongtimetoformafull-faceclosure,allofwhichmayincreasethedeformationofsurroundingrock.Therefore,itisoftennecessarytopre-supportorpre-reinforcetheexcavatedworkingfaceandtherockmassinfrontofitincombinationwithauxiliaryconstructionmeasures.环形开挖预留核心土法要点KeyPoint应该根据初期支护的变形情况或施工安排修筑内层衬砌。Theinnerliningshallbeconstructedaccordingtothedeformationoftheprimarysupportortheconstructionarrangement.分部开挖法PartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved①施作二次支护②上部环形土开挖，初期支护③下台阶开挖，初期支护④核心土开挖施工工序ConstructionProcedures①Constructionofsecondarysupport②Excavationofupperringsoilandprimarysupport③Lowerbenchexcavationandprimarysupport④Coresoilexcavation注意：因为拱形开挖高度较小，或地层松软，锚杆不易成型，所以施工中应不设或少设锚杆。环形开挖进尺为0.5~1.0m。上部核心土和下台阶的距离：双线隧道为一倍洞跨，单线隧道为两倍洞跨。Notes:Asthearchexcavationheightissmall,orthestratumissoft,theanchorrodisnoteasytoform.Theringcutfootageis0.5~1.0m.Thedistancebetweentheuppercoresoilandthelowerbench:onetimetunnelspanintermsofdouble-tracktunnels,anddoubletunnelspanintermsofsingle-tracktunnel.分部开挖法PartialExcavationMethod环形开挖预留核心土法RingCutMethodwithCoreSoilReserved单侧壁双侧壁导坑法SingleSideandDoubleSideHeadingMethod03单侧壁导坑法：单侧壁导坑法一般将断面分成三块，即侧壁导坑①、上台阶②、下台阶③。侧壁导坑的尺寸应本着充分利用台阶的支撑作用，并考虑机械设备和施工条件而定。SingleSideHeadingMethod:Thesinglesideheadingmethodgenerallydividesthesectionintothreeparts,namelysideheading①,upperbench②andlowerbench③.Thesizeofthesideheadingshallbedeterminedbasedonthefulluseofsupportofbenchesandconsideringthemechanicalequipmentandconstructionconditions.分部开挖法PartialExcavationMethod单侧壁双侧壁导坑法SingleSideandDoubleSideHeadingMethod优点：Advantages洞室开挖跨度减小（通过形成闭合支护的侧导坑将隧道断面跨度一分为二），有利于围岩稳定。reductionofexcavationspanofthecavern(thespanofthetunnelsectionisdividedintotwopartsbyformingasideheadingwithclosedsupport),whichisconducivetothestabilityofsurroundingrock.分部开挖法PartialExcavationMethod单侧壁双侧壁导坑法SingleSideandDoubleSideHeadingMethod单侧壁导坑法特点及适用条件：CharacteristicsandApplicableConditionsofSingleSideHeadingMethod:缺点：Disadvantages:增加了材料用量和工程造价；施工进度慢。increasedmaterialconsumptionandprojectcostandslowconstructionprogress.适用条件：Applicableconditions:单侧壁导坑法适用于围岩稳定性较差、断面跨度大、地表沉陷难以控制的软弱松散围岩。Thesinglesideheadingmethodissuitableforweakandloosesurroundingrockswithpoorstability,largesectionspananddifficultcontrolofsurfacesubsidence.双侧壁导坑法：双侧壁导坑法一般将断面分成为四块：左、右侧壁导坑①、上部核心土②、下台阶③。导坑尺寸的拟定原则同单侧壁导坑法一致，但宽度不宜超过断面最大跨度的1/3。DoubleSideHeadingMethod:Thedoublesideheadingmethodgenerallydividesthesectionintofourparts:leftandrightsideheading①,uppercoresoil②,andlowerbench③.Theprinciplesfordeterminingtheheadingsizeisthesameasthatofthesinglesideheadingmethod,butthewidthshouldnotexceed1/3ofthemaximumsectionspan.分部开挖法PartialExcavationMethod单侧壁双侧壁导坑法SingleSideandDoubleSideHeadingMethod缺点：双侧壁导坑法虽施工安全，但受力复杂、工艺要求高、施工速度较慢、成本较高。对于岩石强度低，环境要求高的隧道应采用单臂掘进机、铣挖机、机械破碎等开挖。优点：控制沉降变形好、施工中间变形几乎不发展。双侧壁导坑法特点及适用条件：CharacteristicsandApplicableConditionsofDoubleSideHeadingMethod:Advantages:goodcontrolofsettlementdeformationandlittledevelopmentofdeformationduringconstruction.Disadvantages:Althoughthedoublesideheadingmethodissafeinconstruction,itischaracterizedbycomplexstress,highprocessrequirements,slowconstructionspeedandhighcost.分部开挖法PartialExcavationMethod单侧壁双侧壁导坑法SingleSideandDoubleSideHeadingMethod适用条件：双侧壁导坑法适用于Ⅴ～Ⅵ级围岩双线隧道掘进。Applicableconditions:Thedoublesideheadingmethodissuitablefordouble-tracktunnelingwithClassV~VIsurroundingrock.中洞法MiddleHoleMethod04中洞法：中洞法适用于双连隧道，采用先开挖中洞并支护，在中洞内施工作业隧道中墙混凝土，后开挖两侧的施工方法MiddleHoleMethod:Themiddleholemethodisapplicabletodouble-hingedtunnel,whichisaconstructionmethodtofirstlyexcavateandsupportthemiddlehole,pourmiddlewallconcreteduringconstructioninthemiddlehole,andthenexcavatebothsides.分部开挖法PartialExcavationMethod中洞法MiddleHoleMethod中洞法开挖高度应大于中墙高度1m，开挖宽度应大于5m；Theexcavationheightofthemiddleholemethodshallbe1mgreaterthantheheightofthemiddlewall,andtheexcavationwidthshallbegreaterthan5m;分部开挖法PartialExcavationMethod中洞法MiddleHoleMethod施工要求：ConstructionRequirements:中洞开挖长度根据隧道长度、宽度以及地质情况综合考虑，一般为50~80m；theexcavationlengthwithmiddleholemethodisgenerally50~80maccordingtothetunnellength,widthandgeologicalconditions;中洞开挖后应及时施作初期支护，再分段灌筑中墙混凝土，在中墙混凝土达到设计强度后方可拆模，并进行临时横向支撑。Afterthemiddleholeisexcavated,theprimarysupportshallbeconstructedintime,themiddlewallconcreteshallbepouredinsections,theconcreteframeworkshallberemoveduntildesignedstrengthismet,andtemporarylateralsupportshallbecarriedout.中隔壁法：中隔壁法在近年国内的铁路隧道和城市地下工程的实践中，被证明是通过软弱、浅埋大跨度隧道的最有效的施工法之一，它适用于Ⅴ～Ⅵ级围岩的双线隧道。CenterDiaphragmMethod:Thecenterdiaphragmmethod(CDmethod)isamethodtodividethetunnelintoleftandrightpartsforexcavation,firstlycarryouttwo-partorthree-partlayeredexcavationononesideofthetunnel,erectprimarysupportandtemporarysupportofmiddlediaphragm,thenexcavatetheothersideofthetunnelinbenches,andconstructcorrespondingprimarysupport.分部开挖法PartialExcavationMethod中洞法MiddleHoleMethod4.CenterDiaphragmMethod(CD)suitablefor(shallow-buried)double-tracktunnelswithClassV~VIsurroundingrock.中隔壁法适用条件：ApplicableConditionsofCenterDiaphragmMethod:中隔壁法（CD法）是将隧道分为左右两部分进行开挖，先在隧道一侧采用二部或三部分层开挖，搭建初期支护和中隔壁临时支护，再分台阶开挖隧道另一侧，并进行相应的初期支护的施工方法。Inthepracticeofdomesticrailwaytunnelsandurbanundergroundengineeringinrecentyears,centerdiaphragmmethodisproventobeoneofthemosteffectiveconstructionmethodsforweak,shallow-buriedandlong-spantunnels,anditissuitablefor(shallow-buried)double-tracktunnelswithClassV~VIsurroundingrock.交叉中隔壁法：交叉中隔壁法（CRD法）：在软弱围岩大跨隧道中，先开挖隧道一侧的一部分，搭建好部分中隔壁和横隔板，再开挖隧道另一侧的一部分，完成横隔板施工；然后再开挖最先施工一侧的最后部分，并延长中隔壁，最后开挖剩余部分CrossDiaphragmMethod:Crossdiaphragmmethod(CRDmethod):Inthelong-spantunnelwithweaksurroundingrock,firstlyexcavateapartofonesideofthetunnel,buildcenterdiaphragmandtransversediaphragm,andexcavateapartoftheothersideofthetunneltocompletetheconstructionoftransversediaphragm;thenexcavatethelastpartofthefirstconstructionside,andextendthemiddlediaphragm,andfinally,excavatetheremainingpart.分部开挖法PartialExcavationMethod中洞法MiddleHoleMethod优点：Advantages将大断面施工化成小断面施工，各个局部封闭成环的时间段，控制早期围岩变形，每个步序受力体系完整。Thelargesectionconstructionisconvertedintosmallsectionconstruction,andtheearlydeformationofsurroundingrockiscontrolledineachlocalclosedringperiod,andthestresssystemofeachstepiscomplete.交叉中隔壁法：CrossDiaphragmMetho