《鋼結(jié)構(gòu)安裝》課件-1.2.2 鋼屋架節(jié)點(diǎn)設(shè)計(jì)

1.2.2鋼屋架的節(jié)點(diǎn)設(shè)計(jì)

Jointdesignofsteelrooftruss第一：鋼屋架節(jié)點(diǎn)的設(shè)計(jì)步驟First:thedesignstepsofsteelrooftrussjoints第二：弦桿拼接節(jié)點(diǎn)Second:chordsplicingnodes第三：支座節(jié)點(diǎn)Third:supportnodes鋼結(jié)構(gòu)的節(jié)點(diǎn)隨結(jié)構(gòu)形式的不同而不同。本節(jié)僅對(duì)普通鋼屋架的節(jié)點(diǎn)計(jì)算方法及構(gòu)造作一些簡(jiǎn)單的介紹。Thejointsofthesteelstructurevarywiththedifferentformsofthestructure.Thissectiononlygivessomebriefintroductiontothejointcalculationmethodandstructureofordinarysteelrooftrusses.

一、鋼屋架節(jié)點(diǎn)的設(shè)計(jì)步驟

First:thedesignstepsofsteelrooftrussjoints

（1）根據(jù)腹桿截面和內(nèi)力確定連接焊縫的焊腳尺寸和長(zhǎng)度；Determinethesizeandlengthoftheweldjointsconnectingtheweldaccordingtothestudsectionandinternalforces（2）根據(jù)焊縫的長(zhǎng)度和施工的誤差確定節(jié)點(diǎn)板的形狀和尺寸；Determinetheshapeandsizeofthegussetplateaccordingtothelengthoftheweldandtheerrorofconstruction（3）結(jié)合屋架施工圖繪制進(jìn)行。Combinedwiththedrawingofrooftrussconstructiondrawings.二、弦桿拼接節(jié)點(diǎn)

Second:chordsplicingnodes

弦桿拼接節(jié)點(diǎn)Chordsplicingnodes工地拼接

Sitesplicing工廠拼接Factorysplicing（1）工廠拼接：為了型鋼接長(zhǎng)而設(shè)的桿件接頭，拼接點(diǎn)常設(shè)于內(nèi)力較小的節(jié)間內(nèi)。Factorysplicing:memberjointssetupforsectionsteeljoints,andthesplicingpointsarefixedintheinternodeswithlessinternalforce（2）工地拼接：由于運(yùn)輸條件限制而設(shè)的安裝接頭，拼接點(diǎn)通常設(shè)在屋脊節(jié)點(diǎn)和下弦跨中節(jié)點(diǎn)處。Sitesplicing:Duetotherestrictionsoftransportationconditions,thesplicingpointisusuallylocatedattheridgenodeandthelowerchordspanmiddlenode.屋脊節(jié)點(diǎn)Roofnodes下弦跨中節(jié)點(diǎn)Lowerchordspanmiddlenode大家可以看下圖中的上圖就是鋼屋架的上弦拼接節(jié)點(diǎn)，設(shè)在屋脊處；再看圖中的下圖是下弦拼接節(jié)點(diǎn)，一般設(shè)置在跨中節(jié)點(diǎn)處。Youcanseethattheabovepictureinthefigurebelowisthewindingsplicingnodeofthesteelrooftruss,whichislocatedattheridge;Lookingatthefigurebelow,thefollowingfigureisthelowerchordsplicingnode,whichisgenerallysetatthecross-middlenode.弦桿采用拼接角鋼拼接。拼接角鋼采用的規(guī)格一般與弦桿相同(當(dāng)弦桿截面改變時(shí)，與較小截面弦桿相同)。在施工中，為了使拼接角鋼能貼緊被連接的弦桿和便于施焊，需要截去拼接角鋼的外棱角，并把豎向肢切去mm(其中t是拼接角鋼肢厚，h是角焊縫焊腳尺寸，5mm是為避開弦桿角鋼肢尖的圓角而考慮的切割余量)。拼接時(shí)為正確定位和便于施焊，須設(shè)置臨時(shí)性的安裝螺栓。Thechordissplicedwithsplicedanglesteel.Thespecificationsusedforsplicinganglesteelaregenerallythesameasthechord(thesameasthesmallersectionchordwhenthechordsectionchanges).Inconstruction,inordertomakethesplicinganglesteelfittheconnectedchordandfacilitatewelding,itisnecessarytocutofftheouteredgesandcornersofthesplicedanglesteelandcutofftheverticallimbmm(wheretisthesplicinganglesteellimbthickness,histhefilletweldfootsize,5mmisacuttingallowancetoavoidtheroundedcornersofthesteeltipofthechordangle).Inordertocorrectlypositionandfacilitateweldingduringsplicing,temporarymountingboltsmustbeinstalled

三、支座節(jié)點(diǎn)

Third:supportnodes

加勁肋Stiffeners節(jié)點(diǎn)板Gussetplates錨栓Anchors支座底板Supportbaseplate支座節(jié)點(diǎn)Supportnode加勁肋Stiffeners加勁肋的作用是加強(qiáng)底板的剛度，以便較為均勻地傳遞支座反力并提高節(jié)點(diǎn)板的側(cè)向剛度。加勁肋應(yīng)設(shè)在支座節(jié)點(diǎn)的中心處，加勁肋高度由節(jié)點(diǎn)板尺寸確定，加勁肋厚度取與節(jié)點(diǎn)板相同。肋板底端應(yīng)切角以避免3條互相垂直的角焊縫交于一點(diǎn)。Thefunctionofstiffenersistostrengthenthestiffnessofthebaseplateinordertotransmitthesupportreactionforcemoreevenlyandimprovethelateralstiffnessofthegussetplate.Thestiffenershouldbelocatedinthecenterofthesupportnode,theheightofthestiffenerisdeterminedbythesizeofthegussetplate,andthestiffenerthicknessshouldbethesameasthegussetplate.Thebottomendoftheribplateshouldbecuttoavoid3filletweldsperpendiculartoeachotheratonepoint.2.錨栓Anchors錨栓錨栓預(yù)埋于柱中，其直徑一般取20～25mm。為了便于安裝屋架時(shí)能夠調(diào)整位置，底板上的錨栓孔直徑應(yīng)為錨栓直徑的2～2.5倍。屋架安裝完畢后，在錨栓上套上墊圈，并與底板焊牢以固定屋架，墊圈的孔徑比錨栓直徑大1～2mm。Theanchorisembeddedinthecolumn,anditsdiameterisgenerally20~25mm。Inordertofacilitatethepositiontobeadjustedwheninstallingrooftrusses,thediameteroftheanchorholeonthebottomplateshouldbe2~2.5timesoftheanchordiameter。Aftertherooftrussisinstalled,putawasherontheanchor,andwelditfirmlywiththebottomplatetofixtherooftruss,andtheholediameterofthewasheris1~2mmlargerthanthediameteroftheanchor.3.支座節(jié)點(diǎn)的傳力路徑Theforcetransmissionpathofthesupportnode屋架桿件的內(nèi)力通過連接焊縫傳給節(jié)點(diǎn)板，然后經(jīng)節(jié)點(diǎn)板和加