谈后浇带的设计与施工

..;;谈后浇带的设计与施工Abstract:thenewreleaseof"codefordesignofconcretestructures"(GB50010-2002,hereinafterreferredtoastheconcretespecification),thereinforcedconcretestructureofthelargestjointspacingrequirementsthanthestrictnorms,normsusedbytheword"may"shouldbechangedto"".Thisrequiresinthestructuraldesign,thedesignermustbetakenseriouslyduetolongtostructurethenegativeinfluence,whenthedistanceincreasesorstructuraljointsisnoexpansionjoint,musttakepracticalmeasurestopreventthecracksofthestructure.Keywords:postpouringbelt;design;constructionThenewreleaseof"codefordesignofconcretestructures"(GB50010-2002,hereinafterreferredtoastheconcretespecification),thereinforcedconcretestructureofthelargestjointspacingrequirementsthanthestrictnorms,normsusedbytheword"may"shouldbechangedto"".Thisrequiresinthestructuraldesign,thedesignermustbetakenseriouslyduetolongtostructurethenegativeinfluence,whenthedistanceincreasesorstructuraljointsisnoexpansionjoint,musttakepracticalmeasurestopreventthecracksofthestructure.Inincreasingthespacingofthelargestjointmeasures,takepreventionmeasuresinconstructionstageisaneffectivemethodforthegeneralconcreteshrinkagereducingtheadverseeffectsofourcommonapproachistosettheconstructionofthepouringbelt.Inaddition,whenthebuildingthereisabigdifference,butthestructuredesignaccordingtothespecificcircumstancescannotsetuppermanentdeformationjoints,suchashigh-levelandmulti-storeymainbuilding(orlower)betweenthepodium,constructionisoftenusedafterpouringtoresolvethedifferencesintheconstructionphaseofthesettlement.Thesetwokindsofconstructionafterpouringbelt,theformercanbecalled"shrinkageafterpouringbelt",thelattercanbecalled"postsettlementbelt".Inthispaper,aftertheconstructionofthedesignandconstructionofpouringbelt,combinedwithengineeringpractice,talkabouttheauthor'sview.First,thedesignofthebackpouringbeltWhentheplanesizeofthebuildingstructureexceedsthemaximumspacingoftheexpansionjointspecifiedintheconcretespecification(concretespecification9.1.1),themethodofpostconstructionpouringbeltshallbetakenintoconsiderationtoappropriatelyincreasethespacingoftheexpansionjoint.Butthegeneralstructureduetotemperaturechangesgreatly,sothelargestjointspacingshouldnotbemorethantheconcretespecificationlimitstoomuchatthesametime,weshouldpayattentiontostrengthentheroofinsulation,theexternalwallsoftheuseofreliableandefficientheatpreservation,andincreasingthelongitudinalreinforcementratioofverticalwall,gableroofandotherimportantpartsofthe.Whenthelocalstructureisequippedwithshockproofjointsduetoseismicdesign,thewidthoftheexpansionjointshallmeettherequirementsoftheshockresistantseamwidth.Thestructureofsuperlongbasementisfrequent,inadditiontothebasementroofandinthebasementoftheoutdoorabovegroundwallaffectedbytemperaturechangeisrelativelylarge,thebasementandfoundationofinternalstructureintheusestageaffectedbythechangeoftemperatureinsideandoutsidetheroom,themainproblemstosolveistheconcreteshrinkagestressinfluenceonstructure.Exceptintheconstructionstageofpostpouringbelt,shouldstrengthenthereinforcementofthebasementroofandexteriorwallofbasement,recommendedminimumlongitudinalreinforcementratioofnotlessthan0.5%barasfaraspossibletochooseasmallerdiameter,generally10to16canbe,trytochoosetheclosespacing,shouldnotbegreaterthan150mm,fineanddensethedistributionofreinforcementisfavorableforstructuralcrack.Itmustbepointedoutthat..,Thebackpouringbandcanonlysolvetheautogenousshrinkageofconcreteduringconstruction,anditcannotsolvethestressconcentrationcausedbythechangeoftemperature,andcannotreplacetheexpansionjoint.Itiswrongforsomestructuraldesignerstoequatethebackpouringstripwiththeexpansionjoint,sincetheeffectisnotthesame.Whenthebasementstructureistoolongandthebackpouringbeltisnotenoughtosolvetheconcreteshrinkageandtemperaturevariation,theshrinkagecompensatingconcretecanbetakenintoconsideration,andtheexpansionreinforcingbeltisarrangedinanappropriateplace.Themethodcannotonlyincreasethemaximumspacingoftheexpansionjoint,butalsocanreplacethepartoftheconstructionaftercastingbeltwiththeexpansionstrengtheningbelt,thusrealizingthecontinuouspouringoftheconcrete,namelytheseamlessconstruction.Itshouldbenotedthattheuseofexpansionreinforcingstriptoreplacepartoftheconstructionofthepouringbelt,expansionstrengtheningbeltpositionshouldbesetupinthestructuretemperaturestress,andshoulddeveloptechnicalmeasuresstrictly,ensurethequalityofconcreterawmaterialandmicroexpansionagentmixaccurate,concretepartsofthebasementstructuredesigntherateofexpansionrequirements.Themainbodybetweentallbuildingwithpodiumissetuppermanentdeformationjoints,orsetthesettlementpostpouringbeltintheconstructionphase,theconstructionsiteshouldbebasedonthebearinglayeroffoundationsoilconditions,basicform,arrangementofupperstructureconditionsdetermined.Thelocalfoundationbearinglayersoilbetter,suchashigh-risebuildingfoundationinthebasementrocksorgravellayer,orthepile,smallersettlementdeformationofhigh-risebuildings,thiscanbeconsideredtheconstructionofthepouringbeltisnotsetuppermanentdeformationjoints,high-risebuildingandpodiumFoundation(orbasement)asawhole.Whenthehighcompressibilityoffoundationbearinglayer,andthethicknessislarger,theheightdifferencebetweenthemaintallbuildingwithpodiumthedisparityislarge,high-risebuildingloadislarger,duetothedifferencesbetweenthehigh-risebuildingandthepodiumofthelargersettlement,inthenaturalfoundationconditions,ortosetuppermanentdeformationjointofhigh-risebuildingandpodiumcompletelytornoffforgood.Whenbetweenhigh-risebuildingsandtheadjacentpodiumsetuppermanentdeformationjoint,high-risebuildingsonthebasisofdepthshouldbegreaterthanthepodiumfoundationdepthofatleast2meters,doesnotmeetthecomputationalstabilityofhigh-risebuildingstomeetthisrequirement,andtakemeasurestopreventthereliabilitybetweenthetallbuildingwithpodiumstudentsareinclinedtoeachother.Ioncevisitedaproject,high-risebuildingundergroundlayer,thegroundlayersixteen,alayerofpureundergroundgarage,andthroughthebasementofahigh-risebuilding,whichsetupasettlement,foundationdepthisbasicallythesame,thehardmaterialfillingsettlementjoint.Becausethemutualdumpingbetweenthehigh-risebuildingandtheundergroundgaragehasnotbeensolved,whenthebuildingisputintouse,itisfoundthatthecracksonbothsidesofthesettlementjointarecracking,causingthebasementtoleak.1,high-risebuildingwithpilefoundationorotherfoundationtreatmentmethods,orcompensationbasis,trytoexpandthehigh-risebuildingfoundationandgroundcontactarea,reducethehigh-risebuildingfoundationbottomcontactpressure,andthepodiumisusedshallowsinglecolumnorstripfoundation,adjustthedifferencebetweenthetallbuildingwithpodiumsettlement.2,tominimizethecontactareaoftheskirtpartoffoundationandfoundation,istoincreasethebasisoftheskirtpartofbottomcontactpressure,increasetheamountofthepodiumwas.3,combinedwiththeembeddeddepthrequirementsofhigh-risebuildings,Theheightofthebasementofthehigh-risebuildingisadjustedsothatthegroundbearinglayerfallsonthesoillayerwithsmallcompressibilityandhighbearingcapacityofthefoundation,sothatthesettlementofthehigh-risebuildingcanbeeffectivelyreduced.Inthedesignofgroundfoundation,thestructuraldesignershouldselecttheeconomicandreasonableplaninlightofthespecificconditionsoftheprojectandmanyaspects.Thepostcastingpartsshouldnotbebrokeningeneral,butshouldletthesteelcontinuousthrough,thatis,onlytheconcreteafterthetemporarycutoff.Butsometimesthespecificcircumstancesoftheprojectarenotallowedtopostpouringbelt,suchasroofandfloorengineeringofundergroundgarageareconnectedwiththemainchannel,butforthesmallconstructionsite,notleavingthepostpouringbelt,andrequiretheconstructionunitstobethefirstconstructionofthemainstructure,afterthecompletionofthemainlaneconstruction,theconstructionunitsforthereinforcementandthemainbodyisconnectedtothelatereservation,theuseofweldedconnections,weldedconnectionsreinforcedwiththesamesectionrateshallnotbegreaterthan50%.Someprojectswillbecastinthestripwithallthereinforcementbroken,atthistime,inordertoavoidthesamesectionofreinforced100%connections,itisappropriatetopostpouringwithtwistsandturns,andnotalongastraightlinelayout.Connectionmethodisrecommendedformechanicalconnectionorwelding,butattentionshouldbepaidtoconstructionquality.Whenusinglapjoint,attentionshouldbepaidtothewidthofthebackpouringbelttomeetthelengthoflapjointaccordingtotheconcretespecification.Thecrosssectionofthebasepouringbeltshallbeclearlystatedonthestructuraldesigndrawingsandshallnotbegiventotheconstructionunits.Whentheundergroundwaterlevelishigher,itisbettertosetupwaterproofboardatthebackofthefoundation,andaddanadditionalwaterprooflayer.Two,theconstructionoftheafterpouringbeltDuringconstruction,thequalityofconcretepouringonbothsidesofthebackpouringbeltmustbeguaranteedsoastopreventgroutleakageorconcreteloosening.Afterpouringbeltonbothsidesshouldadoptreinforcedbracketwiremeshpartition,andbythestructuredesignpersonneltodeterminethesectionformonbothsides,whenthebasementwaterproofingforthebasement,shouldnotberetainedafterpouringstraightcha.Theconstructionunitshallassignspecialpersonneltomaintainthecleannessofthepostpouringbelt,preventthecorrosionofthereinforcementinthebackpouringbelt,orthesteelbarisbentandbent.Beforetheclosedafterpouringconstruction,shouldbeafterpouringtheimpuritiesinclean,wellderustingsteel,andbothsidesofconcretecuthair,brushinginterfaceagent,afterpouringconcreteshouldbeonbothsidesoftheconcretestrengthgradeincreasedlevel,andbyaddingamicroexpansiveconcretepouringagent.Whenpouringconcreteinthebackpouringbelt,itisnecessarytocontrolitsenvironmentaltemperaturelowerthantheambienttemperatureofconcretepouringonbothsides,andshouldhaveaspecialpersonresponsibleforit.Afterpouringconcretepouring,attentionshouldbepaidtomaintenancework.Inshort,theconstructiondesignandconstructionofthepouringbeltdirectlyaffectsthesafetyandeconomyofthestructure,designandconstructionunitsshouldbepaidenoughattentionto,thedesignandconstructionofthepouringbelt,ensurethequalityofthestructure.ExpansionjointAuthor:kangna1314releasedate:2005-8-07viewnumber:63from:Theshockproofjointshallbeprovidedwithsufficientwidthaccordingtotheseismicfortificationintensity,structure,materialtype,structuretype,heightofthestructuralelementandelevationdifference,andtheupperstructureofbothsidesshallbecompletelyseparated.Whentheexpansionjointandthesettlementjointaresetup,Itswidthshallbeinaccordancewiththerequirementsofshockproofjoint.Thegravityretainingwallshallbeprovidedwithanexpansionjointateachintervalof10~20m,andasettlementjointshallbeaddedwhenthefoundationischanged.Intheretainingstructurecorner,measuresshouldbetakentostrengthenthestructure.High-risebuildingconcretestructureWheninstallingshockproofjoints,thefollowingrequirementsshallbemet:1minimumwidthofshockproofshallcomplywiththefollowingrequirements:Framestructure,theheightofthehouseisnotmorethan15mparts,itisadvisableto70mm,morethan15mparts,6degrees,7degrees,8degreesand9degrees,correspondingtoeachadditionalheightof5m,4m,3Mand2m,shouldbroaden20mm;2frameshearwallstructure,housingcanbeusedinaccordancewiththefirst70%ofthevalueofthenumericalvalueoftheshearwallstructure,housingcanbeusedinaccordancewiththefirstsetof50%ofthevalue,butthetwoarenotlessthan70mm.Whenthestructuralsystemofbothsidesoftheshockproofjointisdifferent,thewidthoftheshockproofjointshallbedeterminedaccordingtotheunfavorablestructuretype;theheightofthehousesonbothsidesoftheshockproofjointisnotthesame,andthewidthoftheshockproofjointshallbedeterminedaccordingtotheheightofthelowerhousing.Whenthefoundationofadjacentstructureshaslargesettlementdifference,thewidthofvibrationproofjointshouldbeincreased.Shockproofjointsshouldbeinstalledalongthefullheightofthehouse,andthebasementfoundationshallbesecuredwithoutseismicjoints,buttheconstructionandconnectionshallbestrengthenedatthecorrespondingplacewiththeuppershockjoint.Betweenthestructuralunitsorbetweenthemainbuildingandthepodiumwithoutreliablemeasures,shouldnotadoptcorbelpracticesettingshockproofjointjoist.Inseismicdesign,thewidthofexpansionjointandsettlementjointshallbeinaccordancewiththeminimumwidthofshockproofjoint.Constructionofraftfoundationandpodiumfoundationshouldmeetthefollowingrequirements:1whenbetweenhigh-risebuildingsandconnectedtothepodiumsettingsettlementjoint,high-risebuildingfoundationdepthshouldbegreaterthanthepodiumfoundationdepthofatleast2m.Effectivemeasuresmustbetakenwhentherequirementsarenotmet.Theapplicationofgroundsettlementofsandfilling,toensurethereliabilityofthemainfoundationaroundthelateralrestraint;2whenbetweenhigh-risebuildingsandconnectedtothepodiumwithoutsettingsettlementjoint,shouldbepouringinthepodiumsideaftersettingthepostpouringbeltpositionshouldbesetupinthemainbuildingfromthesidecolumnspansecond.TheconcreteinthebackpouringzoneshouldbecalculatedaccordingtothemeasuredsettlementvalueThesettlementdifferencecanmeetthedesignrequirementsandcanbepoured;3whenbetweenhigh-risebuildingsandconnectedtothepodiumisnotallowedtosetthesettlementjointandpostpouringbelt,thefoundationshouldbetakenintoaccountwhencheckingthedeformation,deformationoffoundationandstructureinfluenceeachotherandtakeeffectivemeasures.Maximumdistancebetweenexpansionjointsoftallbuildingstructures:Constructionsystem,constructionmethod,maximumspacingMCast-in-placeframestructure55Castinplaceshearwallstructure45Note:theexpansionjointspacingof1frameshearwallscanbecalculatedaccordingtotheconcretelayoutofthestructure2whentheroofwithoutinsulationorinsulationmeasures,concreteshrinkageorindoorstructureduetoconstructionexposuretimeislonger,expansionjointspacingshouldbeappropriatelyreduced3,locatedindryclimateareas,hotsummerandfrequentrainareastructure,theexpansionjointspacingshouldbeappropriatelyreducedWhenthefollowingconstructionmeasuresandconstructionmeasuresareadoptedtoreducetheinfluenceoftemperatureandconcreteshrinkageonthestructure,thespacebetweentheexpansionjointscanberelaxed:1,thetopfloor,thebottom,gableandlongitudinalwall,theendoftheBay,andothertemperaturechangesinthelargerparts,improvetherateofreinforcement;2,thetoplayertostrengtheninsulationmeasures,Externalinsulationlayerisinstalledonexteriorwall;3,each30~40mspacingleavingtheconstructionafterpouringband,bandwidth800~1000mm,steellapjoint,andafterpouringconcreteshouldbewateredintwomonths;4thetopfloorisdividedintoshortersectionbyusingsmallerstructuralformorlocaltemperaturejointatthetop;5useshrinkagecement,reducecementdosage,addproperadmixtureinconcrete;6improvethestructuralreinforcementratioofeachfloorslaboradoptpartialprestressedstructure.Itisnotsuitabletosetupshockproofjointsforsteelstructuresinhigh-risebuildings.Measuresshouldbetakentoimprovetheseismiccapacityoftheweakparts.Highexpansionsteelstructureshouldnotbeequippedwithexpansionjoints,whenitmustbeinstalled,theseismicstructureexpansionjointsshouldmeettherequirementsofseismicjoints.Noexpansionjointorsettlementjointshallbeinstalledintheprotectionunitoftheairraidbasement.Whenthedoorunitisarrangedbetweentwoadjacentjointsorsettlementjoints,andtheneedtoopenadoor,beprotectivesealingdoorarerespectivelyarrangedonthetwodoorclosedonthewall.Thedistancefromtheclosedoortothedeformationjointshallmeettherequirementsofthedooropening.Ifthetwoprotectionunitprotection,etc.Atthesametime,thehighresistanceprotectiveairtightdoorshouldbelocatedonthesideofthehighresistanceprotectionunit,andthelowresistanceprotectiveairtightdoorshouldbelocatedonthesideofthelowresistanceprotectionunit.Theinstallationofthedeformationjointofthebasementoftheairdefencebasementshallcomplywiththefollowingprovisions.1thesettlementjointandexpansionjointshallnotbeinstalledintheprotectionunit;2,theuppergroundbuildingshallbeprovidedwithexpansionjointsandshockproofjoints,andthebasementcannotbesetup;3roomentranceandthemainstructureofthejointshouldbelocatedinthesettlementjoints;4,reinforcedconcretestructures,expansionjoints,maximumspacingshouldbecarriedoutaccordingtocurrentstandards.MaximumdistancebetweenexpansionjointsofreinforcedconcretestructuresStructureclass,outdoorintheroomorsoilBentframeassemblytype10070Frameassemblytype7550Cast-in-placetype5535Shearwallstructureassemblytype6540Cast-in-placetype4530Retainingwall,basement,wallandotherstructuralassemblytype4030Cast-in-placetype3020Note:1,theoverallexpansionofthestructure,housingexpansionjointspacingshouldbeinaccordancewiththetableofthecurrenttypeofnumericalvalue;2theexpansionjointspaceofframeshearwallstructureorframecoretubestructurecanbecalculatedaccordingtotheconcretelayoutofthestructure;3whentheroofwithoutinsulationorinsulationmeasures,theframestructure,shearwallstructureexpansionjointspacingshouldbecalculatedaccordingtothevalueoftheoutdoorcolumninthetable;4cast-in-placeTiaoyan,raincovertelescopicstructureexposedspacingshouldnotbemorethan12mInthefollowingcases,themaximumgapbetweentheexpansionjointsshallbeproperlyreduced:The1columnheight(fromthetopofthefoundation)iscalculatedtobelessthan8mofthebentstructure;2,theroofwithoutinsulationorinsulationmeasuresofthebentstructure;3structureslocatedindryclimates,hotsummersandfrequentrainstorms,oroftenunderhightemperature;4theshearwallstructureusingslipformconstructiontechnology;5,materialshrinkagelarger,indoorstructureduetoconstructionexposuretimelonger.Ifthereissufficientevidenceandreliablemeasuresforthefollowingcircumstances,themaximumgapbetweentheexpansionjointsonthetableshallbeincreasedappropriately:1concretepouringadoptspostcastingbeltconstruction;2specialprestressmeasuresareadopted;3takemeasurestoreduceconcretetemperaturechangesorshrinkage.Theinfluenceoftemperaturevariationandconcreteshrinkageonthestructureshouldbetakenintoaccountwhentheexpansionjointspacingisincreased.Withtheindependentfoundationofthebentframestructure,whentheexpansionjoints,itsdoublecolumnfoundationcancontinuetoopenMaximumdistancebetweenexpansionjointsofplainconcretestructuresStructureclass,outdoorintheroomorsoilFabricatedstructure4030Castinplacestructure(withstructuralsteel)3020Castinplacestructure(notequippedwithstructuralsteel)2010ThemaximumdistancebetweenexpansionjointsofmasonrybuildingsRooforfloortypespacingAnintegralorassembledreinforcedconcretestructurewitharooforfloorwithinsulationorinsulation.50Aroofwithoutinsulationorinsulation40Assemblytypepurlinsystemofreinforcedconcretestructure,roofinsulationlayerortheinsulatinglayerofthe60floorAroofwithoutinsulationorinsulation60Assemblytypepurlinsystemofreinforcedconcretestructurewithinsulationlayerorinsulatinglayeroftheroof75Aroofwithoutinsulationorinsulation60Tileroof,woodenrooforflatroof,lightsteelroof100Note:1ofbrick,brickandreinforcedmasonrybuildingsfromthevaluesinthetable;thestonemasonry,autoclavedsandlimebrick,autoclavedflyashbrickandconcreteblockbuildingfromthevaluesinthetablemultipliedby0.8coefficient.Whenpracticalexperienceistakenandeffectivemeasuresaretaken,theprovisionsofthistablearenotobserved;2theroofofthereinforcedconcreteroofshallbemadeofreinforcedconcreteroof;3thewallexpansionjointinstalledinthistablecannotpreventthelocalcracksinthewallduetothetemperaturedeformationofthereinforcedconcreteroofandtheshrinkagedeformationofthemasonryatthesametime;4storeyislargerthan5mofsinteredordinarybrick,porousbrick,reinforcedblockmasonrystructure,singlestoreyhouse,itsexpansionjointspacingcanbemultipliedby1.3bythevalueofthetable;5themaximumspacingoftheexpansionjointsofhousesandstructureswithlargetemperaturedifferenceandfrequentchangesinareasandareasnotheatedbycoldareasshallbeappropriatelyreducedaccordingtothevaluesinthetable;6theexpansionjointofthewallshouldcoincidewithotherdeformationjointsofthestructure.Intheprocessofelevation,theexpansionofthegapmustbeensured.MaximumspacingofexpansionjointsforsmallmasonrybuildingsRooforfloortypespacingAnintegralorassembledconcretestructure;aroofwithathermalinsulatinglayerorinsulatinglayer50Aroofwithoutinsulationorinsulation40Assemblytypepurlinconcretestructuresystemwithinsulationlayerortheinsulatinglayeroftheroof60Aroofwithoutinsulationorinsulation50Assemblytypesteelpurlinconcretestructuresystemwithinsulationlayerorinsulatinglayeroftheroof75Aroofwithoutinsulationorinsulation50Claytileorasbestoscementtile,woodrooforfloorcover75Lengthoftemperaturesectionofsteelstructure,singlestoreyhouseandout