主講曾紹武陜西鐵路工程第講連續(xù)梁整課件講解

第22講連續(xù)梁整體構(gòu)造主講：曾紹武

陜西鐵路工程職業(yè)技術(shù)學(xué)院The23rdtalkOverallstructureofthecontinuousbeam任務(wù)1.連續(xù)梁橋受力體系和受力特點(diǎn)任務(wù)2.連續(xù)梁孔跨布置形式任務(wù)3.連續(xù)梁構(gòu)造要求本節(jié)任務(wù)任務(wù)4.連續(xù)梁、懸臂梁、連續(xù)剛構(gòu)橋區(qū)別Task1.ForcesystemandforcecharacteristicsofcontinuousbeambridgeTask2.ContinuousbeamholespanlayoutformTask3.ContinuousbeamconstructionrequirementsTask4.Continuousbeam,cantileverbeam,continuousrigidframebridgedifference

結(jié)構(gòu)輕型，跨越能力大，有效避免砼開(kāi)裂，受力性能好，變形小，伸縮縫少，行車平順舒適，承載能力大，養(yǎng)護(hù)工程量小，抗震能力強(qiáng)等。任務(wù)1解析：Lightweightstructure,largespanability,effectivelyavoidconcretecracking,goodstressperformance,smalldeformation,lessexpansionjoint,smoothandcomfortabledriving,largebearingcapacity,smallmaintenancequantity,strongseismicability.三跨連續(xù)梁橋三孔簡(jiǎn)支梁橋VS由于支點(diǎn)負(fù)彎矩的卸載作用，跨中正彎矩大大減小，恒載、活載均有卸載作用。由于彎矩圖面積的減小，跨越能力增大。超靜定結(jié)構(gòu)，對(duì)基礎(chǔ)變形及溫差荷載較敏感。行車條件好。任務(wù)1解析.連續(xù)梁橋受力體系和受力特點(diǎn)Duetotheunloadingeffectofthenegativebendingmomentofthefulcrum,thepositivebendingmomentofthespanisgreatlyreduced,andtheconstantloadandliveloadhavetheunloadingeffect.Duetothedecreaseofthebendingmomentdiagramarea,thespanabilityincreases.Ultra-staticstructureissensitivetofoundationdeformationandtemperaturedifferenceload.Gooddrivingconditions.1.連續(xù)梁孔跨布置三跨連續(xù)梁：當(dāng)采用箱形截面的三跨連續(xù)梁時(shí)，邊孔跨徑可減小至中孔的0.5-0.7倍。五跨連續(xù)梁橋：比值為：0.65：0.9：1.0。任務(wù)2解析：連續(xù)梁孔跨布置形式1.ArrangementofthecontinuousbeamholespanThree-spancontinuousbeam:whenthethree-spancontinuousbeamwithaboxcrosssectionisused,thespanofthesideholecanbereducedto0.5-0.7timesofthemiddlehole.Five-spancontinuousbeambridge:theratiois:0.65:0.9:1.0.三跨連續(xù)梁Threespancontinuousbeam五跨連續(xù)梁Fivespancontinuousbeam任務(wù)3.連續(xù)梁構(gòu)造要求子任務(wù)1.連續(xù)梁截面形式子任務(wù)2.連續(xù)梁箱梁構(gòu)成及作用子任務(wù)3.連續(xù)梁構(gòu)造尺寸要求子任務(wù)4.連續(xù)梁橫隔梁設(shè)置要求Task3.ContinuousbeamconstructionrequirementsSubtask1.Continuousbeamcross-sectionformSubtask2.StructureandfunctionofcontinuousbeamboxbeamSubtask3.SizerequirementsforcontinuousbeamstructureSubtask4.Continuousbeamtransversepartitionbeamsettingrequirements依據(jù)橋梁的結(jié)構(gòu)體系、跨度、寬度、梁高、施工方法等確定。大跨度連續(xù)梁通常采用箱形斷面。實(shí)體截面：用于小跨度的橋梁（現(xiàn)澆）Physicalsection:bridgeforsmallspan(cast-in-place)空心板截面：常用于15

30m的連續(xù)梁橋（現(xiàn)澆）Hollowslabsection:commonlyusedfor1530mcontinuousbeambridge(cast-in-place)肋式截面：常用跨度在15

30m范圍內(nèi)，常采用預(yù)制架設(shè)施工，并在梁段安裝完成之后，經(jīng)體系轉(zhuǎn)換形成連續(xù)梁。Ribsection:thecommonspaniswithin1530m,oftenusingprefabricatederectionconstruction,andaftertheinstallationofthebeamsection,throughthesystemconversiontoformacontinuousbeam.魚(yú)腹式特點(diǎn)：構(gòu)造簡(jiǎn)單，施工方便，適用于中、小跨度的連續(xù)梁橋。Features:simplestructure,convenientconstruction,suitableformediumandsmallspancontinuousbeambridge.子任務(wù)1解析：連續(xù)梁截面形式Dedeterminedaccordingtothestructuresystem,span,width,beamheightandconstructionmethodofthebridge.Large-spancontinuousbeamsusuallyadoptabox-shapedsection.等高度連續(xù)梁變高度連續(xù)梁等截面連續(xù)梁變高度連續(xù)梁變截面連續(xù)梁梁高不變。具有構(gòu)造、制造和施工簡(jiǎn)便的特點(diǎn)。適用于中等跨度（40

60m左右）的、較長(zhǎng)的橋梁?？砂吹瓤缁虿坏瓤绮贾?。長(zhǎng)橋多采用等跨布置，以簡(jiǎn)化構(gòu)造，統(tǒng)一模式，便于施工。更能適應(yīng)結(jié)構(gòu)的內(nèi)力分布規(guī)律。受力狀態(tài)與其施工時(shí)的內(nèi)力狀態(tài)基本吻合。梁高變化規(guī)律可以是斜（直）線、圓弧線或二次拋物線。箱型截面的底板、腹板和頂板可作成變厚度，以適應(yīng)梁內(nèi)各截面的不同受力要求。VS高跨比h/L(公路：跨中1/30～1/50；中支點(diǎn)1/16～1/25)。Highspanratioh/L(highway:1/30~1/50;[]middlespan1/16~1/25).高跨比h/L(公路：1/15～1/30）High-spanratioh/L(highway:1/15~1/30)子任務(wù)1解析：連續(xù)梁截面形式梁高的選擇Thebeamheightunchanged.Hasthecharacteristicsofsimpleconstruction,manufacturingandconstruction.Suitableformediumspan(about4060m),longerbridge.Itcanbearrangedbytheequalspanortheunequalspan.Longbridgeadoptsisometriclayouttosimplifythestructure,unifiedmodeandfacilitateconstruction.Itcanmoreadapttotheinternalforcedistributionlawofthestructure.Theforcestateisbasicallyconsistentwiththeinternalforcestateduringtheconstruction.Thebeamheightchangelawcanbeoblique(straight)line,circulararclineorsecondaryparabola.LiangGao'schoice橫斷面：板式、肋梁式和箱形板式：實(shí)體截面和空心截面矩形實(shí)體截面（少用）；曲線形整體截面（常用）；適應(yīng)于中、小跨徑、支架施工，空心板用于跨徑為15～30的連續(xù)梁橋。Cross-section:platetype,ribbeamtypeandboxshapePlatetype:solidsectionandhollowsectionRectangularsolidcrosssection(lessuse);Curveoverallsection(commonuse);Adaptfortheconstructionofmediumandsmallspanandsupport,andthehollowplateisusedforthecontinuousbeambridgewithaspanof15~30.肋梁式：預(yù)制方便，預(yù)制架設(shè)，常用跨徑25～50m，梁高取1.5～2.5m。Ribbeamtype:Theprefabricationisconvenient,theprefabricationanderection,thecommonspanis25~50m,thebeamheightis1.5~2.5m.子任務(wù)1解析：連續(xù)梁截面形式橫斷面：板、肋梁式和箱形箱形截面單箱單室橋?qū)捫∮?8m，雙箱單室橋?qū)挒?0左右單箱雙室寬為25m左右.等高箱梁采用直腹板或斜腹板變高度箱梁采用直腹板。.crosssection:Plate,ribbeamtypeandboxshapeBoxsectionSingle-compartmentbridgewidthislessthan18m,Thedouble-boxsingle-compartmentbridgeisabout20wideThesingleboxanddoublecompartmentisabout25mwide.子任務(wù)1解析：連續(xù)梁截面形式具有良好的抗彎和抗扭性能，是預(yù)應(yīng)力混凝土連續(xù)梁橋的主要截面型式單箱，單室，單箱雙室截面，雙箱單室、雙箱雙室、多箱單室等頂板和底板－結(jié)構(gòu)承受正負(fù)彎矩的主要部位腹板－主要承受結(jié)構(gòu)的彎矩剪應(yīng)力以及扭轉(zhuǎn)剪應(yīng)力引起的主拉應(yīng)力梗腋（或稱承托）－設(shè)置在腹板與頂、底板接頭處鋸齒塊－方便預(yù)應(yīng)力張拉錨固子任務(wù)2.連續(xù)梁箱梁斷面構(gòu)成及作用Withthegoodbendingandtorsionresistance,itisthemainsectiontypeofprestressedconcretecontinuousbeambridgeSinglebox,singleroom,singleboxdoubleroomsection,doubleboxsingleroom,doubleboxdoubleroom,multipleboxsingleroom,etcTopplateandbottomplate-themainpartsofthestructurebearingpositiveandnegativebendingmomentsBenal-MaintensilestresscausedbythebendingshearstressandtorsionalshearstressArshaft(orsupport)-setatthejointbetweenthewebandtopandbottomplateSawblock-facilitateprestressedtensionanchorage箱形斷面的構(gòu)成頂板滿足橫向抗彎及縱向抗壓要求；一般采用等厚度，主要由橫向抗彎控制（橋面板）。腹板主要承擔(dān)剪應(yīng)力和主拉應(yīng)力；一般采用變厚度腹板：靠近跨中處受構(gòu)造要求控制，靠近支點(diǎn)處受主拉應(yīng)力控制，需加厚。底板滿足縱向抗壓要求；一般采用變厚度，跨中主要受構(gòu)造要求控制，支點(diǎn)主要受縱向壓應(yīng)力控制，需加厚。一般在支點(diǎn)截面設(shè)置橫隔板。橫隔板Meettherequirementsofhorizontalbendingresistanceandlongitudinalcompressionresistance;Generallyuseequalthickness,mainlycontrolledbythehorizontalbendingresistance(bridgedeck).Mainlybeartheshearstressandthemaintensilestress;Generallyusethevariablethicknessweb:nearthemiddleofthespaniscontrolledbythestructurerequirements,nearthefulcrumiscontrolledbythemaintensilestress,needtobethickened.Meettherequirementsoflongitudinalcompressionresistance;Generally,thevariablethicknessisadopted,andthespanismainlycontrolledbythestructuralrequirements,andthefulcrumismainlycontrolledbythelongitudinalcompressionstress,whichneedstobethickeneGenerally,thehorizontalpartitionplateissetinthefulcrumsection.箱梁斷面圖Boxbeamsectiondiagram縱斷面：等截面及變截面等截面：跨徑40～60m，構(gòu)造簡(jiǎn)單，施工快捷；立面布置以等跨徑為宜；不等跨布置時(shí)，邊跨：中跨≥0.6，高跨比1/15～1/25；適應(yīng)于支架施工、逐跨架設(shè)施工、移動(dòng)模架施工及頂推施工。變截面：大跨徑預(yù)應(yīng)力砼連續(xù)梁橋，底面曲線為圓弧線、二次拋物線及折線等?？讖轿恢茫哼吙祝褐锌?0.5～0.8；高跨比：跨中截面為1/30～1/50，支點(diǎn)截面為1/15～1/25.子任務(wù)3.連續(xù)梁構(gòu)造尺寸Longitudinalsection:equalsectionandvariablesectionconstantsection:spanof40~60m,simplestructure,fastconstruction;Facadelayoutwithequalspanisappropriate;[]unequalspanlayout,sidespan:middlespan0.[]6,highspanratio1/15~1/25;Adaptforsupportconstruction,spanerectionconstruction,mobileformworkconstructionandjackingconstruction.variablecross-section:Large-spanprestressedconcretecontinuousbeambridge,thebottomcurveforthecirculararc,secondaryparabolaandbrokenline,etc.Aoreposition:sidehole:middlehole=0.[]5~0.[]8;Highspanratio:themidspansectionis1/30~1/50,andthefulcrumsectionis1/15~1/25.T形和I形截面：抗扭剛度小，為增加整體性和分布荷載，設(shè)置中隔梁和端橫梁，肋寬12-20cm。箱形截面：抗彎及抗扭剛度大，為加強(qiáng)橋面板和各箱間的聯(lián)系，可在箱間設(shè)置數(shù)道橫隔梁。T-shapedandI-shapedsection:smalltorsionalstiffness,inordertoincreasetheintegrityanddistributionload,setthemiddlepartitionbeamandendbeam,ribwidth12-20cm.Boxsection:largebendingandtorsionalstiffness,inordertostrengthentheconnectionbetweenthebridgedeckandtheboxes,severaltransversebeamscanbesetbetweentheboxes.子任務(wù)4.連續(xù)梁橫隔板設(shè)置要求連續(xù)梁箱梁橫隔Continuousbeamboxgirdertransversepartition以變截面施工圖為例介紹連續(xù)梁橋構(gòu)造要求Theconstructiondrawingofvariablesectionistakenasanexampletointroducetheconstructionrequirementsofcontinuousbeambridge連續(xù)剛構(gòu)橋特點(diǎn)橋跨結(jié)構(gòu)（主梁）和墩臺(tái)（支柱）整體相連的橋梁叫做剛架橋。豎向荷載下將在主梁端部產(chǎn)生負(fù)彎矩，跨中正彎矩減小，跨中截面尺寸減小。橋墩在豎向荷載下承壓和彎。FeaturesofacontinuousrigidstructurebridgeThebridgeconnectingthespanstructure(mainbeam)andthepier(pillar)ofthewholeiscalledtherigidbridge.Theverticalloadwillproducenegativebendingmomentattheendofthemainbeam,reducingthepositivebendingmomentofthespanandthesizeofthespansection.Thepiersareunderpressureandbendingunderverticalload.任務(wù)4.連續(xù)梁橋、懸臂梁橋、連續(xù)剛構(gòu)橋區(qū)別連續(xù)梁受力特點(diǎn)橋跨結(jié)構(gòu)（主梁）和墩臺(tái)（支柱）整體不相連，橋跨彎矩不傳遞給橋墩。豎向荷載下將在主梁端部產(chǎn)生負(fù)彎矩，跨中正彎矩減小，跨中截面尺寸減小。橋墩在豎向荷載下承壓。Thebridgespanstructure(mainbeam)andthepier(pillar)arenotconnected,andthebendingmomentofthebridgespanisnottransmittedtothebridgepier.Theverticalloadwillproducenegativebendingmomentattheendofthemainbeam,reducingthepositivebendingmomentofthespanandthecrosssectionsizeofthespan.Thebridgepierisunderpressureundertheverticalload.適用范圍較大的橋下凈空，建筑高度受到限制的立交橋、高架橋。超靜定結(jié)構(gòu)，受砼收縮、徐變、溫度、墩臺(tái)不均勻沉陷、預(yù)應(yīng)力和施工結(jié)構(gòu)體系轉(zhuǎn)換時(shí)產(chǎn)生次內(nèi)力。對(duì)基礎(chǔ)條件要求高。優(yōu)點(diǎn)外形尺寸小、橋下凈空大，橋下視野開(kāi)闊，砼用量少，鋼筋用量大，基礎(chǔ)造價(jià)高。scopeofapplicationLargeclearanceunderthebridge,thebuildingheightislimitedbytheoverpass,viaduct.Superstaticstructure,byconcreteshrinkage,creep,tempera