《鋼結(jié)構(gòu)安裝》課件-1.3.2 支座節(jié)點

1.3.2支座節(jié)點

Supportnode第一：壓力支座節(jié)點First:pressuresupportnode第二：拉力支座節(jié)點Second:tensilesupportnode鋼結(jié)構(gòu)中的支座節(jié)點一般采用鉸節(jié)點，盡量采用傳力可靠、連接簡單的構(gòu)造形式。Thesupportnodesinthesteelstructuregenerallyadopthingenodes,andtrytoadoptthestructuralformofreliableforcetransmissionandsimpleconnection.

一、壓力支座節(jié)點

First:pressuresupportnode

常用的壓力支座節(jié)點有以下幾種構(gòu)造形式：Commonlyusedpressuresupportnodeshavethefollowingconstructionforms1.平板支座節(jié)點：通過十字節(jié)點板和底板將支座反力傳給下部結(jié)構(gòu)。Platesupportnodes:Thesupportreactionforceistransmittedtothesubstructurethroughthecrossgussetplateandthebaseplate.優(yōu)點：節(jié)點構(gòu)造簡單，加工方便，用鋼量省。Advantages:simplenodestructure,convenientprocessing,andeconomicalamountofsteel.缺點：節(jié)點處不能轉(zhuǎn)動，受力后會產(chǎn)生一定的彎矩，與計算假定相差較大，可用于較小跨度的網(wǎng)架中。Disadvantages:Thenodecannotrotate,andacertainbendingmomentwilloccuraftertheforce,whichisdifferentfromthecalculationassumptionandcanbeusedinthegridframewithasmallerspan.焊接空心球壓力支座Weldhollowballpressuresupports焊接鋼板壓力支座Weldedsteelplatepressuresupport柱頭上的預(yù)埋螺栓僅起定位作用，安裝就位后應(yīng)將底板與下部支承面板焊牢Theembeddedboltsonthecolumnheadonlyplayapositioningrole,andthebottomplateshouldbeweldedfirmlytothelowersupportpanelafterinstallationinplace2.單面弧形壓力支座節(jié)點Single-sidedarcpressuresupportnode在平板壓力支座的基礎(chǔ)上，在節(jié)點底板和下部支承面板間設(shè)一弧形墊塊而成。適用于中、小跨度網(wǎng)架。Onthebasisoftheplatepressuresupport,anarc-shapedpadisprovidedbetweenthenodebottomplateandthelowersupportpanel.Suitableformediumandsmallspangrids.這種支座節(jié)點在壓力的作用下，支座底板沿墊塊弧面可以轉(zhuǎn)動，下部支承面板上的壓力比較均勻，但摩擦力仍然較大。為了保證支座節(jié)點的轉(zhuǎn)動，柱頭上預(yù)埋螺栓應(yīng)設(shè)在弧形墊塊中心線上，支座底板上的螺栓孔可做成橢圓形，使支座節(jié)點有微量的平移。Undertheactionofpressure,thesupportbottomplatecanrotatealongthearcsurfaceofthepad,andthepressureonthelowersupportpanelisrelativelyuniform,butthefrictionisstilllarge.Inordertoensuretherotationofthesupportnode,theembeddedboltonthecolumnheadshouldbesetonthecenterlineofthearcwasher,andtheboltholeonthesupportbottomplatecanbemadeintoanovalshape,sothatthesupportnodehasasmallamountoftranslation.3.雙面弧形壓力支座節(jié)點（搖擺支座節(jié)點）Double-sidedarcpressuresupportnode(swingsupportnode)

當(dāng)網(wǎng)架的跨度較大、溫度應(yīng)力影響顯著、周邊約束較強時，需要選擇一種既能自由伸縮又能自由轉(zhuǎn)動的支座節(jié)點形式。Whenthespanofthegridframeislarge,theinfluenceoftemperaturestressissignificant,andtheperipheralconstraintisstrong,itisnecessarytochooseasupportnodeformthatcanbothfreelyexpandandrotate.缺點：節(jié)點構(gòu)造復(fù)雜，施工麻煩、造價較高。對抗震不利，在我國應(yīng)用較少。Disadvantages:Thenodestructureiscomplex,theconstructionistroublesome,andthecostishigh.ItisnotgoodforearthquakeresistanceandislessusedinChina.3.雙面弧形壓力支座節(jié)點（搖擺支座節(jié)點）Double-sidedarcpressuresupportnode(swingsupportnode)構(gòu)造：在支座底板和柱頂面板間設(shè)一塊上下均為弧形的鑄鋼板，然后用螺栓將支座上、下支承托板和雙面弧形鑄鋼板三者練成整體。支座上、下支承板開有橢圓孔，使支座節(jié)點在荷載和溫度變化的作用下既可以轉(zhuǎn)動又可以作一定的側(cè)移。Structure:Acaststeelplatewitharc-shapedupperandlowerlevelsissetbetweenthesupportbottomplateandthecolumntoppanel,andthentheupperandlowersupportplatesandthedouble-sidedarccaststeelplatearetrainedintoawholebybolts.Theupperandlowerbearingplatesofthesupportareopenedwithellipticalholes,sothatthesupportnodescanrotateandmakecertainlateralshiftsundertheactionofloadandtemperaturechanges.4.球鉸壓力支座節(jié)點Ballhingepressuresupportnode

對于多支點大跨度網(wǎng)架，為了能使支座節(jié)點適應(yīng)各個方向的自由轉(zhuǎn)動，需使支座與柱頂鉸接而不產(chǎn)生彎矩，常做成球鉸壓力支座。Forthemulti-fulcrumlong-spangrid,inordertoadaptthesupportnodetothefreerotationinalldirections,itisnecessarytohingethesupportwiththetopofthecolumnwithoutgeneratingbendingmoment,anditisoftenmadeintoaballhingepressuresupport.構(gòu)造：由置于柱頂面板上的一個半圓球與一個連于節(jié)點底板上凹形半球的鑄鋼塊相互嵌合，用4個螺栓固定，并在螺帽下設(shè)置彈簧墊圈而組成。利于抗震。Structure:Itconsistsofasemi-circularballplacedonthetoppanelofthecolumnandacaststeelblockconnectedtoaconcavehemisphereonthebaseplateofthenode,fixedwith4bolts,andaspringwasherisprovidedunderthenut.Goodforearthquakeresistance.5.板式橡膠支座節(jié)點Platerubbersupportnode在柱頂面板與節(jié)點板間設(shè)置一塊橡膠墊板組成，適用于大、中跨度網(wǎng)架。目前在國內(nèi)應(yīng)用較廣。Arubberpadissetbetweenthecolumntoppanelandthegussetplate,whichissuitableforlargeandmediumspangridframes.Atpresent,itiswidelyusedinChina優(yōu)點：構(gòu)造簡單、安裝方便、節(jié)省鋼材、造價較低。Advantages:simplestructure,easyinstallation,savingsteel,lowcost.構(gòu)造：橡膠墊板由多層橡膠片和薄鋼板粘合、壓制而成，節(jié)點底板和下部支承用螺栓連接。橡膠墊板具有良好的彈性，也可產(chǎn)生較大的剪切變形，因而既可以滿足網(wǎng)架支座節(jié)點的轉(zhuǎn)動要求，又可以在外界水平力的作用下產(chǎn)生一定的側(cè)向位移。Structure:Therubbergasketisbondedandpressedbymulti-layerrubbersheetandthinsteelplate,andthebottomplateandthelowersupportofthenodeareconnectedbybolts.Therubbergaskethasgoodelasticityandcanalsoproducelargesheardeformation,soitcannotonlymeettherotationrequirementsofthegridsupportnode,butalsoproduceacertainlateraldisplacementundertheactionofexternalhorizontalforce.二、拉力支座節(jié)點Second:tensilesupportnode

網(wǎng)架的支座節(jié)點一般均傳遞壓力，但周邊簡支的正交斜放類網(wǎng)架在角隅處往往會產(chǎn)生拉力，因此在設(shè)計時應(yīng)根據(jù)支承點的受力特點設(shè)計拉力支座節(jié)點。

Thesupportnodesofthegridframegenerallytransmitpressure,buttheorthogonalobliquegridframeofthesurroundingsimplesupportoftengeneratestensileforceatthecorner,sothetensionsupportnodeshouldbedesignedaccordingtotheforcecharacteristicsofthesupportpointwhendesigning.1.平板拉力支座節(jié)點：對于小跨度網(wǎng)架，支座處拉力一般較小，可用平板拉力支座節(jié)點。Flatplatetensionsupportnode:Forsmallspangridframe,thetensionatthesupportisgenerallysmall,andtheflatpullsupportnodecanbeused.該節(jié)點利用錨固螺栓承受拉力。拉