教学单元 2 市政管道开槽施工 Teaching Unit 2 Municipal Pipeline Trenching Construction-2.4 沟槽支撑 2.4 Trench Suppor47课件讲解

教学单元2市政管道开槽施工TeachingUnit2:MunicipalPipelineTrenchingConstruction2.4

沟槽支撑2.4TrenchSupport【教学目标】[TeachingObjectives]通过本单元的学习：Bystudyingthisunit,youwill:1.掌握开槽施工的工序；1.Mastertheproceduresoftrenchexcavation;2.开槽施工的技术措施；2.Learnthetechnicalmeasuresfortrenchexcavation;3.明沟排水方法；3.Understandopentrenchdrainagemethods;4.轻型井点降水设计方法与布置要求；4.Learnthedesignmethodsandlayoutrequirementsforlightwellpointdewatering;5.沟槽开挖土方量计算方法及开挖要求；5.Understandthemethodsforcalculatingtrenchexcavationearthworkvolumeandexcavationrequirements;6.沟槽支撑的支设与拆除方法；6.Learnthemethodsforinstallingandremovingtrenchsupports;7.管道铺设与接口方法；7.Understandpipelinelayingandjointingmethods;8.管道检验方法与要求；8.Learnthemethodsandrequirementsforpipelineinspection;9.沟槽土方回填的要求与方法；9.Understandtherequirementsandmethodsfortrenchbackfilling;10.熟悉柔性排水管道施工方法。10.Familiarizeyourselfwithflexibledrainagepipelineconstructionmethods.向前Forward结尾End向后Backward开端Beginning2.4沟槽支撑2.4TrenchSupport定义：

Definition:支撑是由木材或钢材制成的防止沟槽土壁坍塌的一种临时性挡土结构。

Supportsaretemporaryretainingstructuresmadeofwoodorsteeltopreventtrenchwallcollapse.考虑因素：

Considerations:土质、地下水情况、槽深、槽宽、开挖方法、排水方法、地面荷载等。

Soilquality,groundwaterconditions,trenchdepth,trenchwidth,excavationmethods,drainagemethods,surfaceloads,etc.结构要求：

StructuralRequirements:牢固可靠，支撑材料的质地和尺寸合格；

Sturdyandreliable,withsupportmaterialsmeetingqualityanddimensionalstandards;在保证安全的前提下，节约用料，宜采用工具式钢支撑；

Economicaluseofmaterialswhileensuringsafety;tool-typesteelsupportsarepreferred;便于支设和拆除及后续工序的操作。

Easytoinstallandremove,andfacilitatessubsequentoperations.一、支撑种类及适用条件1.TypesofSupportsandApplicableConditions2.4沟槽支撑2.4TrenchSupport向前Forward结尾End向后Backward开端Beginning1、横撑1.HorizontalBracing由撑板（挡土板）、立柱和撑杠组成。Composedofretainingboards(shoringboards),standcolumns,andstruts.挡土板放置位置PlacementofRetainingBoards{断续式Intermittent连续式Continuous断续式横撑的适用场合：ApplicableConditionsforIntermittentHorizontalBracing:——适用于土质较好，地下水含量较小的黏性土且挖土深度小于3m的沟槽或基坑。—Suitableforcohesivesoilswithgoodqualityandlowgroundwatercontent,andtrenchorpitdepthslessthan3meters.横撑图HorizontalBracingDiagram1-撑板；2-立柱；3-工具式撑杠1-RetainingBoard;2-StandColumn;3-Tool-typeStrut连续式横撑的适用场合：ApplicableConditionsforContinuousHorizontalBracing:——较潮湿的或散粒土及挖土深度不大于5m的沟槽。—Suitablefordamporgranularsoilsandtrencheswithexcavationdepthsnotexceeding5meters.一、支撑种类及适用条件1.TypesofSupportsandApplicableConditions2.4沟槽支撑2.4TrenchSupport挖槽到一定深度或接近地下水位时，开始支设，然后逐层开挖逐层支设。Begininstallationofsupportswhenthetrenchreachesacertaindepthorapproachesthegroundwaterlevel,thenproceedwithexcavationandsupportinstallationlayerbylayer.竖撑支设时：先在沟槽两侧将撑板垂直打入土中，然后开始挖土。Forverticalbracinginstallation:first,drivetheretainingboardsverticallyintothesoilonbothsidesofthetrench,thenbeginexcavation.经常检查槽壁和支撑的情况，尤其在流砂地段或雨后。如支撑各部件有弯曲、倾斜、松动时，应立即加固，拆换受损部件。如发现槽壁有塌方预兆，应加设支撑，而不应倒拆支撑。Frequentlycheckthetrenchwallsandsupports,especiallyinquicksandareasorafterrain.Ifanycomponentofthesupportisbent,tilted,orloose,reinforceimmediatelyandreplacedamagedparts.Ifsignsofwallcollapsearedetected,addsupportsinsteadofremovingthem.二、支撑的设置和拆除2.InstallationandRemovalofSupports2.4沟槽支撑2.4TrenchSupport横撑HorizontalBracing竖撑VerticalBracing1、支撑的设置1.InstallationofSupports二、支撑的设置和拆除2.InstallationandRemovalofSupports倒撑：在施工过程中更换立柱和撑扛位置。ReverseSupport:Repositioningstandcolumnsandstrutsduringconstruction.使用场合：原支撑妨碍下一工序进行；ApplicableConditions:Originalsupporthindersthenextprocess;原支撑不稳定；Originalsupportisunstable;一次拆撑有危险；Removingsupportallatonceisdangerous;其他原因必须重新安设支撑。Otherreasonsrequirereinstallationofsupports.2、倒撑2.ReverseSupport2.4沟槽支撑2.4TrenchSupport支撑的拆除：RemovalofSupports:支撑拆除的基本要求：BasicRequirementsforRemovingSupports:检查槽壁有无裂缝，有危险时先还土；Inspectthetrenchwallsforcracks;backfillthesoilifthereisanydanger.多层支撑的沟槽，可自下而上逐层拆除；Fortrencheswithmultiplelayersofsupports,removethemlayerbylayerfromthebottomup.拆撑前要仔细检查沟槽两侧的建筑物、电杆及其他外管道是否安全，必要时要加固后再拆撑；Beforeremovingsupports,carefullyinspectthebuildings,utilitypoles,andotherexternalpipelinesonbothsidesofthetrenchforsafety.Reinforceifnecessarybeforeremoval.沟槽内工作全部完成后，才可将支撑拆除。拆撑与沟槽回填同时进行，边填边拆。拆撑时必须注意安全，继续排除地下水，避免材料损耗。遇撑板和立木较长时，可在还土后或倒撑后拆除。Supportsshouldonlyberemovedafterallworkwithinthetrenchiscompleted.Removalofsupportsandtrenchbackfillingshouldbedonesimultaneously,withfillingandremovaloccurr