《鋼結構安裝》課件-1.2.1 節(jié)點設計的基本知識

1.2.1鋼結構的節(jié)點設計

Jointdesignofsteelstructure

第一：節(jié)點的作用First:theroleofnodes第二：節(jié)點的設計要求Second:thedesignrequirementsofthenode第三：節(jié)點設計的具體內容Third:thespecificcontentofnodedesign鋼結構是由若干構件連接而成，鋼構件又是由若干型鋼或零件連接而成。鋼結構的連接有焊縫連接、鉚釘連接和螺栓連接，連接部位統(tǒng)稱為節(jié)點。Thesteelstructureiscomposedofseveralcomponentsconnected,andthesteelcomponentsareconnectedbyseveralsectionsorparts.Theconnectionofsteelstructurehasweldconnection,rivetconnectionandboltconnection,andtheconnectionpartiscollectivelyreferredtoasthenode.鋼結構steelstructure鋼構件Steelmembers若干型鋼或零件Severalsectionsorparts通過焊接、螺栓連接或鉚接Bywelding,boltingorriveting組成compose連接部位統(tǒng)稱為節(jié)點Theconnectionpartsarecollectivelyreferredtoasnodes

合理的節(jié)點設計對鋼結構的安全度、制作安裝、工程進度、用鋼量指標以及工程造價都有直接的影響。Reasonablenodedesignhasadirectimpactonthesafetyofsteelstructure,productionandinstallation,projectprogress,steelconsumptionindexandprojectcost.一、節(jié)點的作用

FirstTheroleofthenode2傳遞荷載Transferloads1連接匯交桿件Connectthejunctionmembers

二、節(jié)點的設計要求

First

Designrequirementsforthenode

2保證匯交桿件交于一點，不產生附加彎矩Ensurethattheintersectionmemberisdeliveredatonepointwithoutadditionalbendingmoments3構造簡單，制作簡便，安裝方便Simplestructure,simpleproduction,easyinstallation4耗鋼量少，造價低廉，造型美觀Lesssteelconsumption,lowcost,beautifulshape1受力合理、傳力明確，務必使節(jié)點構造與所采用的計算假定盡量符合，使節(jié)點安全可靠Theforceisreasonableandtheforcetransmissionisclear,andthenodestructuremustbeconsistentwiththecalculationassumptionsusedasmuchaspossibletomakethenodesafeandreliable焊接連接Solderedconnections焊條的選用應該與被連接金屬材質適應：Thechoiceofweldingrodshouldbeadaptedtothemetalmaterialtobejoined

E43——Q235E50——Q345E55——Q390和Q420當不同的兩種鋼材連接時，宜采用與低強度鋼材相適應的焊條！Whendifferenttwosteelsareconnected,itisadvisabletouseweldingrodsthatarecompatiblewithlow-strengthsteels!對接焊縫分為焊透焊縫和非焊透焊縫，其中焊透焊縫特點：強度高，受力性能好，用于承受動力荷載作用的焊接結構，尤為有利Buttweldsaredividedintothrough-weldandnon-through-weldseams,ofwhichthrough-weldcharacteristicsare:highstrength,goodforceperformance,andweldedstructuresthatareusedtowithstanddynamicloads,whichareparticularlybeneficial三、節(jié)點設計的具體內容Third

Thespecificsofthenodedesign角焊縫Filletwelds對接焊縫Buttwelds焊接weld對焊接連接的構造要求：Constructionrequirementsforweldedconnections:1.焊縫的布置盡量對稱于構件或節(jié)點板截面中和軸，避免連接偏心受力；Thearrangementoftheweldisassymmetricalaspossibletothecomponentorgussetplatesectionandtheaxistoavoidtheeccentricforceoftheconnection;2.焊縫長度和焊腳尺寸應由計算及適當?shù)挠嗔看_定，不得任意加大加厚焊縫；Thelengthoftheweldandthesizeoftheweldfootshallbedeterminedbycalculationandappropriatemargin,andtheweldshallnotbearbitrarilyincreasedandthickened;對焊接連接的構造要求：3.為便于焊接操作，盡量選用俯焊、平焊或橫焊的焊接位置，并有合理的施焊空間；Inordertofacilitateweldingoperations,trytochoosetheweldingpositionofpitchwelding,flatweldingorhorizontalwelding,andthereisareasonableweldingspace;4.選用的焊接材料的材質應與主體金屬相適應；Thematerialoftheweldingmaterialselectedshouldbecompatiblewiththebodymetal5.其他構造要求符合設計要求。Otherconstructionrequirementsmeetthedesignrequirements.2.螺栓連接Boltedconnection

螺栓連接Boltedconnection普通螺栓一般分為A、B、C三級，A、B為精制螺栓，C為粗制螺栓。普通螺栓連接一般采用C級螺栓，其螺栓連接的制孔應采用鉆孔Ordinaryboltsaregenerallydividedintothreelevels:A,B,C,A,Barerefinedbolts,Cisroughbolts.OrdinaryboltedconnectionsgenerallyuseC-classbolts,andtheholesfortheirboltedconnectionsshouldbedrilled普通螺栓抗剪性能差，不宜用于重要的抗剪連接結構中。對有防松要求的普通螺栓連接，應采用彈簧墊圈或雙螺帽以防止松動Ordinaryboltshavepoorshearresistanceandarenotsuitableforimportantshearconnectionstructures.Forordinaryboltedconnectionswithanti-looseningrequirements,springwashersordoublenutsshouldbeusedtopreventloosening高強度螺栓連接High-strengthboltedconnection普通螺栓連接Normalboltedconnection高強度螺栓的使用日益廣泛，常用8.8S和10.9S兩個強度等級。高強度螺栓最小規(guī)格為Ml2，常用的高強度螺栓為M16-M30。超大規(guī)格的螺栓性能不穩(wěn)定，設計中應慎重使用。在栓焊共用的節(jié)點中，對高強度螺栓臨近焊縫的節(jié)點連接，應當用先擰后焊的工序，并且高強度螺栓的承載力應降低10%考慮。Theuseofhigh-strengthboltsisbecomingmoreandmoreextensive,andtwostrengthgradesof8.8Sand10.9Sarecommonlyused.Theminimumspecificationofhigh-strengthboltsisMl2,andthecommonlyusedhigh-strengthboltsareM16-M30.Theperformanceofoversizedboltsisunstableandshouldbeusedcautiouslyindesign.Inthenodessharedbyboltwelding,thejointconnectionofhigh-strengthboltsneartheweldshouldbescrewedfirstandthenwelded,andthebearingcapacityofhigh-strengthboltsshouldbereducedby10%.3.連接板Connecttheplate連接板起著桿件或構件間保證可靠傳力的重要作用。Theconnectingplateplaysanimportantroleinensuringreliableforcetransmissionbetweenmembersorcomponents其構造原則應符合:傳力直接，中心交匯，外形應力求簡單；不應有凹角，以免產生應力集中；連接布置不應或盡量少產生附加偏心或焊接應力等要求。Itsconstructionprinciplesshouldconformto:directforcetransmission,centerintersection,andsimpleshape;Thereshouldbenoconcavecornerstoavoidstressconcentration;Theconnectionarrangementshouldnotorminimizetherequirementsofadditionaleccentricityorweldingstress.梁腹板應驗算栓孔處腹板的凈截面抗剪。承壓型高強度螺栓連接還須驗算孔壁局部承壓Thebeamwebshouldbemeasuredforthenetcross-sectionalshearresistanceofthewebatthebolthole。Pressure-bearinghigh-strengthboltedconnectionsmustalsoverifythelocalpressureoftheholewall.4.梁腹板Beamweb梁腹板Beamweb梁腹板螺栓孔Beam