教學(xué)單元2市政管道開槽施工TeachingUnit2:MunicipalPipelineTrenchingConstruction2.4

溝槽支撐2.4TrenchSupport【教學(xué)目標(biāo)】[TeachingObjectives]通過本單元的學(xué)習(xí)：Bystudyingthisunit,youwill:1.掌握開槽施工的工序；1.Mastertheproceduresoftrenchexcavation;2.開槽施工的技術(shù)措施；2.Learnthetechnicalmeasuresfortrenchexcavation;3.明溝排水方法；3.Understandopentrenchdrainagemethods;4.輕型井點(diǎn)降水設(shè)計(jì)方法與布置要求；4.Learnthedesignmethodsandlayoutrequirementsforlightwellpointdewatering;5.溝槽開挖土方量計(jì)算方法及開挖要求；5.Understandthemethodsforcalculatingtrenchexcavationearthworkvolumeandexcavationrequirements;6.溝槽支撐的支設(shè)與拆除方法；6.Learnthemethodsforinstallingandremovingtrenchsupports;7.管道鋪設(shè)與接口方法；7.Understandpipelinelayingandjointingmethods;8.管道檢驗(yàn)方法與要求；8.Learnthemethodsandrequirementsforpipelineinspection;9.溝槽土方回填的要求與方法；9.Understandtherequirementsandmethodsfortrenchbackfilling;10.熟悉柔性排水管道施工方法。10.Familiarizeyourselfwithflexibledrainagepipelineconstructionmethods.向前Forward結(jié)尾End向后Backward開端Beginning2.4溝槽支撐2.4TrenchSupport定義：

Definition:支撐是由木材或鋼材制成的防止溝槽土壁坍塌的一種臨時(shí)性擋土結(jié)構(gòu)。

Supportsaretemporaryretainingstructuresmadeofwoodorsteeltopreventtrenchwallcollapse.考慮因素：

Considerations:土質(zhì)、地下水情況、槽深、槽寬、開挖方法、排水方法、地面荷載等。

Soilquality,groundwaterconditions,trenchdepth,trenchwidth,excavationmethods,drainagemethods,surfaceloads,etc.結(jié)構(gòu)要求：

StructuralRequirements:牢固可靠，支撐材料的質(zhì)地和尺寸合格；

Sturdyandreliable,withsupportmaterialsmeetingqualityanddimensionalstandards;在保證安全的前提下，節(jié)約用料，宜采用工具式鋼支撐；

Economicaluseofmaterialswhileensuringsafety;tool-typesteelsupportsarepreferred;便于支設(shè)和拆除及后續(xù)工序的操作。

Easytoinstallandremove,andfacilitatessubsequentoperations.一、支撐種類及適用條件1.TypesofSupportsandApplicableConditions2.4溝槽支撐2.4TrenchSupport向前Forward結(jié)尾End向后Backward開端Beginning1、橫撐1.HorizontalBracing由撐板（擋土板）、立柱和撐杠組成。Composedofretainingboards(shoringboards),standcolumns,andstruts.擋土板放置位置PlacementofRetainingBoards{斷續(xù)式Intermittent連續(xù)式Continuous斷續(xù)式橫撐的適用場(chǎng)合：ApplicableConditionsforIntermittentHorizontalBracing:——適用于土質(zhì)較好，地下水含量較小的黏性土且挖土深度小于3m的溝槽或基坑。—Suitableforcohesivesoilswithgoodqualityandlowgroundwatercontent,andtrenchorpitdepthslessthan3meters.橫撐圖HorizontalBracingDiagram1-撐板；2-立柱；3-工具式撐杠1-RetainingBoard;2-StandColumn;3-Tool-typeStrut連續(xù)式橫撐的適用場(chǎng)合：ApplicableConditionsforContinuousHorizontalBracing:——較潮濕的或散粒土及挖土深度不大于5m的溝槽?！猄uitablefordamporgranularsoilsandtrencheswithexcavationdepthsnotexceeding5meters.一、支撐種類及適用條件1.TypesofSupportsandApplicableConditions2.4溝槽支撐2.4TrenchSupport挖槽到一定深度或接近地下水位時(shí)，開始支設(shè)，然后逐層開挖逐層支設(shè)。Begininstallationofsupportswhenthetrenchreachesacertaindepthorapproachesthegroundwaterlevel,thenproceedwithexcavationandsupportinstallationlayerbylayer.豎撐支設(shè)時(shí)：先在溝槽兩側(cè)將撐板垂直打入土中，然后開始挖土。Forverticalbracinginstallation:first,drivetheretainingboardsverticallyintothesoilonbothsidesofthetrench,thenbeginexcavation.經(jīng)常檢查槽壁和支撐的情況，尤其在流砂地段或雨后。如支撐各部件有彎曲、傾斜、松動(dòng)時(shí)，應(yīng)立即加固，拆換受損部件。如發(fā)現(xiàn)槽壁有塌方預(yù)兆，應(yīng)加設(shè)支撐，而不應(yīng)倒拆支撐。Frequentlycheckthetrenchwallsandsupports,especiallyinquicksandareasorafterrain.Ifanycomponentofthesupportisbent,tilted,orloose,reinforceimmediatelyandreplacedamagedparts.Ifsignsofwallcollapsearedetected,addsupportsinsteadofremovingthem.二、支撐的設(shè)置和拆除2.InstallationandRemovalofSupports2.4溝槽支撐2.4TrenchSupport橫撐HorizontalBracing豎撐VerticalBracing1、支撐的設(shè)置1.InstallationofSupports二、支撐的設(shè)置和拆除2.InstallationandRemovalofSupports倒撐：在施工過程中更換立柱和撐扛位置。ReverseSupport:Repositioningstandcolumnsandstrutsduringconstruction.使用場(chǎng)合：原支撐妨礙下一工序進(jìn)行；ApplicableConditions:Originalsupporthindersthenextprocess;原支撐不穩(wěn)定；Originalsupportisunstable;一次拆撐有危險(xiǎn)；Removingsupportallatonceisdangerous;其他原因必須重新安設(shè)支撐。Otherreasonsrequirereinstallationofsupports.2、倒撐2.ReverseSupport2.4溝槽支撐2.4TrenchSupport支撐的拆除：RemovalofSupports:支撐拆除的基本要求：BasicRequirementsforRemovingSupports:檢查槽壁有無裂縫，有危險(xiǎn)時(shí)先還土；Inspectthetrenchwallsforcracks;backfillthesoilifthereisanydanger.多層支撐的溝槽，可自下而上逐層拆除；Fortrencheswithmultiplelayersofsupports,removethemlayerbylayerfromthebottomup.拆撐前要仔細(xì)檢查溝槽兩側(cè)的建筑物、電桿及其他外管道是否安全，必要時(shí)要加固后再拆撐；Beforeremovingsupports,carefullyinspectthebuildings,utilitypoles,andotherexternalpipelinesonbothsidesofthetrenchforsafety.Reinforceifnecessarybeforeremoval.溝槽內(nèi)工作全部完成后，才可將支撐拆除。拆撐與溝槽回填同時(shí)進(jìn)行，邊填邊拆。拆撐時(shí)必須注意安全，繼續(xù)排除地下水，避免材料損耗。遇撐板和立木較長(zhǎng)時(shí)，可在還土后或倒撐后拆除。Supportsshouldonlyberemovedafterallworkwithinthetrenchiscompleted.Removalofsupportsandtrenchbackfillingshouldbedonesimultaneously,withfillingandremovaloccurr