教學單元2市政管道開槽施工TeachingUnit2:MunicipalPipelineTrenchingConstruction2.4

溝槽支撐2.4TrenchSupport【教學目標】[TeachingObjectives]通過本單元的學習：Bystudyingthisunit,youwill:1.掌握開槽施工的工序；1.Mastertheproceduresoftrenchexcavation;2.開槽施工的技術措施；2.Learnthetechnicalmeasuresfortrenchexcavation;3.明溝排水方法；3.Understandopentrenchdrainagemethods;4.輕型井點降水設計方法與布置要求；4.Learnthedesignmethodsandlayoutrequirementsforlightwellpointdewatering;5.溝槽開挖土方量計算方法及開挖要求；5.Understandthemethodsforcalculatingtrenchexcavationearthworkvolumeandexcavationrequirements;6.溝槽支撐的支設與拆除方法；6.Learnthemethodsforinstallingandremovingtrenchsupports;7.管道鋪設與接口方法；7.Understandpipelinelayingandjointingmethods;8.管道檢驗方法與要求；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性擋土結構。

Supportsaretemporaryretainingstructuresmadeofwoodorsteeltopreventtrenchwallcollapse.考慮因素：

Considerations:土質、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.結構要求：

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

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

Economicaluseofmaterialswhileensuringsafety;tool-typesteelsupportsarepreferred;便于支設和拆除及后續工序的操作。

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{斷續式Intermittent連續式Continuous斷續式橫撐的適用場合：ApplicableConditionsforIntermittentHorizontalBracing:——適用于土質較好，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連續式橫撐的適用場合：ApplicableConditionsforContinuousHorizontalBracing:——較潮濕的或散粒土及挖土深度不大于5m的溝槽。—Suitablefordamporgranularsoilsandtrencheswithexcavationdepthsnotexceeding5meters.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，開始支設，然后逐層開挖逐層支設。Begininstallationofsupportswhenthetrenchreachesacertaindepthorapproachesthegroundwaterlevel,thenproceedwithexcavationandsupportinstallationlayerbylayer.豎撐支設時：先在溝槽兩側將撐板垂直打入土中，然后開始挖土。Forverticalbracinginstallation:first,drivetheretainingboardsverticallyintothesoilonbothsidesofthetrench,thenbeginexcavation.經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、松動時，應立即加固，拆換受損部件。如發現槽壁有塌方預兆，應加設支撐，而不應倒拆支撐。Frequentlycheckthetrenchwallsandsupports,especiallyinquicksandareasorafterrain.Ifanycomponentofthesupportisbent,tilted,orloose,reinforceimmediatelyandreplacedamagedparts.Ifsignsofwallcollapsearedetected,addsupportsinsteadofremovingthem.二、支撐的設置和拆除2.InstallationandRemovalofSupports2.4溝槽支撐2.4TrenchSupport橫撐HorizontalBracing豎撐VerticalBracing1、支撐的設置1.InstallationofSupports二、支撐的設置和拆除2.InstallationandRemovalofSupports倒撐：在施工過程中更換立柱和撐扛位置。ReverseSupport:Repositioningstandcolumnsandstrutsduringconstruction.使用場合：原支撐妨礙下一工序進行；ApplicableConditions:Originalsupporthindersthenextprocess;原支撐不穩定；Originalsupportisunstable;一次拆撐有危險；Removingsupportallatonceisdangerous;其他原因必須重新安設支撐。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，有危險時先還土；Inspectthetrenchwallsforcracks;backfillthesoilifthereisanydanger.多層支撐的溝槽，可自下而上逐層拆除；Fortrencheswithmultiplelayersofsupports,removethemlayerbylayerfromthebottomup.拆撐前要仔細檢查溝槽兩側的建筑物、電桿及其他外管道是否安全，必要時要加固后再拆撐；Beforeremovingsupports,carefullyinspectthebuildings,utilitypoles,andotherexternalpipelinesonbothsidesofthetrenchforsafety.Reinforceifnecessarybeforeremoval.溝槽內工作全部完成后，才可將支撐拆除。拆撐與溝槽回填同時進行，邊填邊拆。拆撐時必須注意安全，繼續排除地下水，避免材料損耗。遇撐板和立木較長時，可在還土后或倒撐后拆除。Supportsshouldonlyberemovedafterallworkwithinthetrenchiscompleted.Removalofsupportsandtrenchbackfillingshouldbedonesimultaneously,withfillingandremovaloccurr