隧道施工技術TunnelConstructionTechnologyPartialExcavationMethod分部開挖法分部開挖法目錄TableofContentsPartialExcavationMethod分部開挖法的概念和分類1ConceptandClassificationofPartialExcavationMethod環形開挖預留核心土法2RingCutMethodwithCoreSoilReserved單側壁雙側壁導坑法3SingleSideandDoubleSideHeadingMethod中洞法4MiddleHoleMethod課程小結5Summary分部開挖法的概念和分類ConceptandClassificationofPartialExcavationMethod01分部開挖法PartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved單側壁、雙側壁導坑法SingleSideandDoubleSideHeadingMethod中洞法MiddleHoleMethodCD法、CRD法CDmethod,CRDmethod分部開挖法是把設計的巷（隧）道斷面劃分成若干部分，進行二次及其以上開挖，最后達到巷（隧）道設計開挖斷面的一種施工方法。Partialexcavationmethodisamethodtodividethedesignedroadway(tunnel)sectionintoseveralpartstocarryoutthesecondaryandaboveexcavation,andfinally,reachthedesignexcavationsectionoftheroadway(tunnel).分部開挖法PartialExcavationMethod分部開挖法的概念和分類ConceptandClassificationofPartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved02環形開挖預留核心土法一般將斷面分成為環形拱部、上部核心土、下部臺階三部分。Theringcutmethodwithcoresoilreservedgenerallydividesthesectionintothreeparts:ringarch,uppercoresoilandlowerbench.環形開挖預留核心土法RingCutMethodwithCoreSoilReserved1——上部弧形導坑開挖1–Excavationofupperarchheading2——上部左側導坑開挖2–Excavationofupperleftheading3——上部右側導坑開挖3–Excavationofupperrightheading4——上部核心土開挖4–Excavationofuppercoresoil5——下部開挖5–Lowerexcavation分部開挖法PartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved環形開挖預留核心土法優點Advantages在環形開挖預留核心土法中，因為上部留有核心土支撐著開挖面，而且能迅速、及時地建造拱部初期支護，所以開挖的工作面穩定性好。核心土和下部開挖都是在拱部初期支護保護下進行的，施工安全性好。臺階長度相對較長，以減少上、下臺階施工的干擾；同時該方法施工機械化程度較高，施工速度較快。Intheringcutmethodwithcoresoilreserved,thestabilityoftheexcavatedworkingfaceisgoodbecausethecoresoilisreservedintheupperparttosupporttheexcavationfaceandtheprimarysupportofthearchcanbeconstructedquicklyandtimely.Thecoresoilandtheexcavationofthelowerpartarebothcarriedoutundertheprimarysupportprotectionofthearch,andtheconstructionissafe.Thebenchisrelativelylongtoreducetheinterferenceofupperandlowerbenchconstruction.Meanwhile,themechanizationdegreeofconstructionwiththemethodishighandtheconstructionspeedisfast.特點及適用條件CharacteristicsandApplicableConditions分部開挖法PartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved環形開挖預留核心土法缺點Disadvantages雖然核心土增強了開挖面的穩定，但是，開挖過程中圍巖要經受多次擾動，而且斷面分塊多，支護結構形成全斷面封閉的時間長，這些都有可能使圍巖變形增大。因此，它常需要結合輔助施工措施對開挖工作面及其前方巖體進行預支護或預加固。Althoughthecoresoilenhancesthestabilityoftheexcavationface,thesurroundingrockwillsuffermultipledisturbancesduringexcavation,thesectionisdividedintomultipleparts,andthesupportstructuretakesalongtimetoformafull-faceclosure,allofwhichmayincreasethedeformationofsurroundingrock.Therefore,itisoftennecessarytopre-supportorpre-reinforcetheexcavatedworkingfaceandtherockmassinfrontofitincombinationwithauxiliaryconstructionmeasures.環形開挖預留核心土法要點KeyPoint應該根據初期支護的變形情況或施工安排修筑內層襯砌。Theinnerliningshallbeconstructedaccordingtothedeformationoftheprimarysupportortheconstructionarrangement.分部開挖法PartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved①施作二次支護②上部環形土開挖，初期支護③下臺階開挖，初期支護④核心土開挖施工工序ConstructionProcedures①Constructionofsecondarysupport②Excavationofupperringsoilandprimarysupport③Lowerbenchexcavationandprimarysupport④Coresoilexcavation注意：因為拱形開挖高度較小，或地層松軟，錨桿不易成型，所以施工中應不設或少設錨桿。環形開挖進尺為0.5~1.0m。上部核心土和下臺階的距離：雙線隧道為一倍洞跨，單線隧道為兩倍洞跨。Notes:Asthearchexcavationheightissmall,orthestratumissoft,theanchorrodisnoteasytoform.Theringcutfootageis0.5~1.0m.Thedistancebetweentheuppercoresoilandthelowerbench:onetimetunnelspanintermsofdouble-tracktunnels,anddoubletunnelspanintermsofsingle-tracktunnel.分部開挖法PartialExcavationMethod環形開挖預留核心土法RingCutMethodwithCoreSoilReserved單側壁雙側壁導坑法SingleSideandDoubleSideHeadingMethod03單側壁導坑法：單側壁導坑法一般將斷面分成三塊，即側壁導坑①、上臺階②、下臺階③。側壁導坑的尺寸應本著充分利用臺階的支撐作用，并考慮機械設備和施工條件而定。SingleSideHeadingMethod:Thesinglesideheadingmethodgenerallydividesthesectionintothreeparts,namelysideheading①,upperbench②andlowerbench③.Thesizeofthesideheadingshallbedeterminedbasedonthefulluseofsupportofbenchesandconsideringthemechanicalequipmentandconstructionconditions.分部開挖法PartialExcavationMethod單側壁雙側壁導坑法SingleSideandDoubleSideHeadingMethod優點：Advantages洞室開挖跨度減小（通過形成閉合支護的側導坑將隧道斷面跨度一分為二），有利于圍巖穩定。reductionofexcavationspanofthecavern(thespanofthetunnelsectionisdividedintotwopartsbyformingasideheadingwithclosedsupport),whichisconducivetothestabilityofsurroundingrock.分部開挖法PartialExcavationMethod單側壁雙側壁導坑法SingleSideandDoubleSideHeadingMethod單側壁導坑法特點及適用條件：CharacteristicsandApplicableConditionsofSingleSideHeadingMethod:缺點：Disadvantages:增加了材料用量和工程造價；施工進度慢。increasedmaterialconsumptionandprojectcostandslowconstructionprogress.適用條件：Applicableconditions:單側壁導坑法適用于圍巖穩定性較差、斷面跨度大、地表沉陷難以控制的軟弱松散圍巖。Thesinglesideheadingmethodissuitableforweakandloosesurroundingrockswithpoorstability,largesectionspananddifficultcontrolofsurfacesubsidence.雙側壁導坑法：雙側壁導坑法一般將斷面分成為四塊：左、右側壁導坑①、上部核心土②、下臺階③。導坑尺寸的擬定原則同單側壁導坑法一致，但寬度不宜超過斷面最大跨度的1/3。DoubleSideHeadingMethod:Thedoublesideheadingmethodgenerallydividesthesectionintofourparts:leftandrightsideheading①,uppercoresoil②,andlowerbench③.Theprinciplesfordeterminingtheheadingsizeisthesameasthatofthesinglesideheadingmethod,butthewidthshouldnotexceed1/3ofthemaximumsectionspan.分部開挖法PartialExcavationMethod單側壁雙側壁導坑法SingleSideandDoubleSideHeadingMethod缺點：雙側壁導坑法雖施工安全，但受力復雜、工藝要求高、施工速度較慢、成本較高。對于巖石強度低，環境要求高的隧道應采用單臂掘進機、銑挖機、機械破碎等開挖。優點：控制沉降變形好、施工中間變形幾乎不發展。雙側壁導坑法特點及適用條件：CharacteristicsandApplicableConditionsofDoubleSideHeadingMethod:Advantages:goodcontrolofsettlementdeformationandlittledevelopmentofdeformationduringconstruction.Disadvantages:Althoughthedoublesideheadingmethodissafeinconstruction,itischaracterizedbycomplexstress,highprocessrequirements,slowconstructionspeedandhighcost.分部開挖法PartialExcavationMethod單側壁雙側壁導坑法SingleSideandDoubleSideHeadingMethod適用條件：雙側壁導坑法適用于Ⅴ～Ⅵ級圍巖雙線隧道掘進。Applicableconditions:Thedoublesideheadingmethodissuitablefordouble-tracktunnelingwithClassV~VIsurroundingrock.中洞法MiddleHoleMethod04中洞法：中洞法適用于雙連隧道，采用先開挖中洞并支護，在中洞內施工作業隧道中墻混凝土，后開挖兩側的施工方法MiddleHoleMethod:Themiddleholemethodisapplicabletodouble-hingedtunnel,whichisaconstructionmethodtofirstlyexcavateandsupportthemiddlehole,pourmiddlewallconcreteduringconstructioninthemiddlehole,andthenexcavatebothsides.分部開挖法PartialExcavationMethod中洞法MiddleHoleMethod中洞法開挖高度應大于中墻高度1m，開挖寬度應大于5m；Theexcavationheightofthemiddleholemethodshallbe1mgreaterthantheheightofthemiddlewall,andtheexcavationwidthshallbegreaterthan5m;分部開挖法PartialExcavationMethod中洞法MiddleHoleMethod施工要求：ConstructionRequirements:中洞開挖長度根據隧道長度、寬度以及地質情況綜合考慮，一般為50~80m；theexcavationlengthwithmiddleholemethodisgenerally50~80maccordingtothetunnellength,widthandgeologicalconditions;中洞開挖后應及時施作初期支護，再分段灌筑中墻混凝土，在中墻混凝土達到設計強度后方可拆模，并進行臨時橫向支撐。Afterthemiddleholeisexcavated,theprimarysupportshallbeconstructedintime,themiddlewallconcreteshallbepouredinsections,theconcreteframeworkshallberemoveduntildesignedstrengthismet,andtemporarylateralsupportshallbecarriedout.中隔壁法：中隔壁法在近年國內的鐵路隧道和城市地下工程的實踐中，被證明是通過軟弱、淺埋大跨度隧道的最有效的施工法之一，它適用于Ⅴ～Ⅵ級圍巖的雙線隧道。CenterDiaphragmMethod:Thecenterdiaphragmmethod(CDmethod)isamethodtodividethetunnelintoleftandrightpartsforexcavation,firstlycarryouttwo-partorthree-partlayeredexcavationononesideofthetunnel,erectprimarysupportandtemporarysupportofmiddlediaphragm,thenexcavatetheothersideofthetunnelinbenches,andconstructcorrespondingprimarysupport.分部開挖法PartialExcavationMethod中洞法MiddleHoleMethod4.CenterDiaphragmMethod(CD)suitablefor(shallow-buried)double-tracktunnelswithClassV~VIsurroundingrock.中隔壁法適用條件：ApplicableConditionsofCenterDiaphragmMethod:中隔壁法（CD法）是將隧道分為左右兩部分進行開挖，先在隧道一側采用二部或三部分層開挖，搭建初期支護和中隔壁臨時支護，再分臺階開挖隧道另一側，并進行相應的初期支護的施工方法。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）：在軟弱圍巖大跨隧道中，先開挖隧道一側的一部分，搭建好部分中隔壁和橫隔板，再開挖隧道另一側的一部分，完成橫隔板施工；然后再開挖最先施工一側的最后部分，并延長中隔壁，最后開挖剩余部分CrossDiaphragmMethod:Crossdiaphragmmethod(CRDmethod):Inthelong-spantunnelwithweaksurroundingrock,firstlyexcavateapartofonesideofthetunnel,buildcenterdiaphragmandtransversediaphragm,andexcavateapartoftheothersideofthetunneltocompletetheconstructionoftransversediaphragm;thenexcavatethelastpartofthefirstconstructionside,andextendthemiddlediaphragm,andfinally,excavatetheremainingpart.分部開挖法PartialExcavationMethod中洞法MiddleHoleMethod優點：Advantages將大斷面施工化成小斷面施工，各個局部封閉成環的時間段，控制早期圍巖變形，每個步序受力體系完整。Thelargesectionconstructionisconvertedintosmallsectionconstruction,andtheearlydeformationofsurroundingrockiscontrolledineachlocalclosedringperiod,andthestresssystemofeachstepiscomplete.交叉中隔壁法：CrossDiaphragmMetho