主講曾紹武陜西鐵路工程第講支架現(xiàn)澆課件講解

主講：曾紹武

陜西鐵路工程職業(yè)技術(shù)學(xué)院第24講支架現(xiàn)澆法施工Lesson24Constructionwithcast-in-placesupportmethodSpeaker:ZengShaowuShaanxiRailwayEngineeringVocationalandTechnicalCollege任務(wù)導(dǎo)入

通過對現(xiàn)澆支架施工的學(xué)習(xí)，掌握現(xiàn)澆預(yù)應(yīng)力混凝土梁的支架法施工工藝及注意事項．Bystudyingtheconstructionofcast-in-placebrackets,mastertheconstructionprocessandprecautionsofthebracketmethodforcast-in-placeprestressedconcretebeamsTaskImport能力目標(biāo)能夠掌握支架類型適用條件目標(biāo)１目標(biāo)２能夠掌握支架施工工藝目標(biāo)３能夠了解支架監(jiān)控要點支架現(xiàn)澆法施工CapabilityobjectivesAbletograsptheapplicableconditionsofbrackettypesAbletomastertheconstructionprocessofbracketsAbletounderstandthekeypointsofbracketmonitoringSupportcast-in-placeconstructionmethod任務(wù)1.支架現(xiàn)澆法適用條件任務(wù)2.支架的類型及適用條件任務(wù)3.支架法施工工藝及實施方案本節(jié)任務(wù)資訊Task1.Applicableconditionsforcast-in-placesupportmethodTask2.TypesandApplicableConditionsofSupportsTask3.Constructionprocessandimplementationplanofsupportmethod就地澆注施工是必須有的，在偏僻山區(qū)，大型吊裝設(shè)備不能就住的地方。變寬度橋、彎橋等復(fù)雜結(jié)構(gòu)橋梁城市彎曲曲橋等不能用裝配法施工的，則采用支架現(xiàn)澆方法。非標(biāo)準(zhǔn)跨徑采用裝配法成本較高。Cast-in-placeconstructionisnecessary,asinremotemountainousareas,largeliftingequipmentcannotbeeasilyaccommodated.Forcomplexstructuralbridgessuchasvariablewidthbridgesandcurvedbridgesthatcannotbeconstructedusingassemblymethodsinurbancurvedbridges,thebracketcast-in-placemethodisused.Thecostofusingassemblymethodfornon-standardspansisrelativelyhigh.任務(wù)1.支架現(xiàn)澆法適用條件Task1.Applicableconditionsforcast-in-placesupportmethod

就地澆筑混凝土梁橋的上部結(jié)構(gòu)，首先應(yīng)在橋孔位置搭設(shè)支架，以支承模板、澆筑的鋼筋混凝土以及其他施工荷載的重力。Theupperstructureofcast-in-placeconcretebeambridgesshouldfirstbesupportedbybracketsatthebridgeopeningtosupportthegravityoftheformwork,pouredreinforcedconcrete,andotherconstructionloads.

支架support按其構(gòu)造分Dividedbyitsstructure立柱式梁式梁式－立柱式按其材料分木支架鋼支架鋼木支架萬能桿件組拼支架

（備注：還應(yīng)進(jìn)行強(qiáng)度和穩(wěn)定性驗算）任務(wù)2.支架的類型及適用條件SPARTask2.TypesandApplicableConditionsofSupportsBeamtypeBeamcolumntypeAccordingtoitsmaterialclassificationsupportSteelBracketSteelandwoodbracketsUniversalrodassemblybracket任務(wù)2.支架的類型及適用條件子任務(wù)1.立柱式支架及適用條件子任務(wù)2.梁式支架及適用條件子任務(wù)3.梁柱式支架及適用條件Task2.TypesandApplicableConditionsofSupportsSubtask1.PillarSupportandApplicableConditionsSubtask2.BeamSupportandApplicableConditionsSubtask3.Beamcolumnsupportandapplicableconditions思考選擇合適的支架？

情境1（橋一）30+45+30m連續(xù)梁橋，雙圓柱橋墩柱高2-8m，直徑1.4m，橋下無水。

情境2（橋二15+25+15m連續(xù)梁橋，雙圓柱橋墩，墩高35-60m，直徑1.4m，橋下有水。情境3（橋三）：

45+80+45連續(xù)梁橋，雙柱矩形橋墩，墩高10-15m以上，直徑1.4m，橋下無水，主跨下有二級公路通過。Thinkaboutchoosingtheappropriatebracket?Scenario1(Bridge1)30+45+30mcontinuousbeambridge,doublecylindricalbridgeThepiercolumnis2-8mhighwithadiameterof1.4m,andthereisnowaterunderthebridge.Scenario2(BridgeII15+25+15mcontinuousbeambridge,doublecylindricalpier,Thepierhasaheightof35-60mandadiameterof1.4m,withwaterunderthebridge.Scenario3(Bridge3):45+80+45continuousbeambridge,doublecolumnrectangularBridgepier,withaheightof10-15mormoreandadiameterof1.4m,withoutwaterunderthebridge,Second-classhighwaypassesunderthemainspan.立柱式支架特點和適用條件：構(gòu)造簡單，搭設(shè)拆卸均較方便。一般用于旱地或不通航河流及橋墩不高的情況。組成：支架整體由排架和縱梁組成，而排架由柱、樁和蓋梁組成。PillarbracketFeaturesandapplicationconditions:Simplestructure,easyinstallationanddisassembly.Generallyusedindryland,navigablerivers,andsituationswherebridgepiersarenothigh.Composition:Thebracketiscomposedofabentframeandlongitudinalbeams,whilethebentframeiscomposedofcolumns,piles,andcoverbeams.立柱式支架圖例:Legendofcolumnbracket:底座墊木和U型底托BasematandU-shapedbottomsupport特點和適用條件：根據(jù)跨徑的不同，梁可采用工字鋼、鋼板梁或鋼桁梁。組成：梁，預(yù)留托架。構(gòu)造布置：工字鋼用于L≤10m，鋼板梁用于L≤20m，鋼桁梁用于L>20m。梁支承于墩旁支柱上，也可支承于橋墩的預(yù)留托架上。子任務(wù)2.梁式支架Characteristicsandapplicableconditions:Accordingtothedifferentspans,beamscanbemadeofI-beams,steelplatebeams,orsteeltrussbeams.Composition:beam,reservedbracket.Structuralarrangement:I-beamforL≤10m,steelplatebeamforL≤20m,andsteeltrussbeamforL>20m.Thebeamissupportedonthepillarnexttothepier,andcanalsobesupportedonthereservedbracketofthebridgepier.Subtask2.Beambracket梁式支架圖例:

Legendofbeambracket:特點和適用條件：當(dāng)橋梁較高，跨徑較大或必須在支承下通航，排洪時應(yīng)采用梁—柱式支架。組成：將梁支承于支柱或臨時支墩上，形成多跨的梁—柱式支架，落架一般用木楔、木馬或砂筒等。子任務(wù)3.梁柱式支架Subtask3.BeamcolumnsupportCharacteristicsandapplicableconditions:Whenthebridgeishigh,hasalargespan,ormustbenavigableundersupport,beamcolumnsupportshouldbeusedforflooddischarge.Composition:Thebeamissupportedonapillarortemporarypiertoformamultispanbeamcolumnsupport,whichisusuallyloweredusingwoodenwedges,woodenhorses,orsandcylinders.梁--柱式支架Beamcolumnsupport支架的布置根據(jù)梁截面大小并通過計算確定以確保強(qiáng)度，剛度，穩(wěn)定性滿足要求，考慮混凝土重量外，還需考慮模板及支架重量，施工荷載（人，料，機(jī)等），作用模板上，支架上的風(fēng)力，其他可能產(chǎn)生的荷載。2.支架設(shè)計與搭設(shè)：2.Supportdesignandinstallation:Thelayoutofthesupportisdeterminedbasedonthecross-sectionalsizeofthebeamandcalculatedtoensurethatthestrength,stiffness,andstabilitymeettherequirements.Inadditiontoconsideringtheweightofconcrete,itisalsonecessarytoconsidertheweightoftheformworkandsupport,constructionloads(personnel,materials,machinery,etc.),thewindforceactingontheformworkandsupport,andotherpossibleloads.支架預(yù)壓加荷示意圖Schematicdiagramofbracketpreloadingandloading支架預(yù)壓整體圖示Overalldiagramofbracketpreloading

支架預(yù)壓示意圖Schematicdiagramofbracketpreloading5.預(yù)拱度設(shè)置及模板安裝支架受力后將發(fā)生彈性變形和非彈性變形，使還未生成強(qiáng)度的橋跨結(jié)構(gòu)在自重作用下隨之發(fā)生變形，為使所施工梁體在卸模后能夠獲得較滿意的設(shè)計文件規(guī)定的外形，故應(yīng)對支架設(shè)置預(yù)拱度。5.CambersettingandformworkinstallationAfterthesupportissubjectedtoforce,itwillundergoelasticandnonelasticdeformation,causingthebridgespanstructurethathasnotyet