设计汇编9外文翻译

[11]xiu-jie.Discussaboutqualitycontrolofboredpilesconstruction.Journalofjiaxingcollege.2002Pickto:combinedwithboredpilesinactualconstructionqualityproblem,putforwardthecorrespondingpreventionmeasures,thispaperdiscussesthefillingpileconstructionqualitycontrolpoints.:boredpiles;Construction;Quality.libraryclassificationTU753.Boredpilesisdirectlyinthedesignofpilelocatedinopenhole,thenputinholeandreinforcingcageandpourconcreteintoapilefoundation.ThiskindofpilefoundationinBridgesandotherprojects,themostbasicstructureofboredpiles.Suchasthreebridge,rainbowbridge,TaiShiQiaoandsoon.Thispapersummarizestheboredpilesintheactualconstructionoftenpronetoqualitycommonfaultandpreventionandcontrolmeasuresareputforward,andhopeforsomeofotherboredpilesconstructiontechnologyisofcertainreferencevaluetotheproblem.OneofthecommonqualitycommonfaultofboredInviewofthecast-in-cepileinpracticalengineeringsitepreparation,drilling,holecleaningtopouringunderwaterconcreteandsooneachlink,correspondingtothequalitycommonfault:offset,superthick,concretesegregationofdregdepositedatthebottomofthebore,pilebodyconcrete plete(includingsandwich,necking,exposureofpile,concreteisweak,loose,piletopconcretereinforcingcageup-floating),etc.Theexistenceoftheseproblems,itisleadtotheunderlyingcausesoftheaccident.Soyoumustcontroltheoccurrenceoftheseproblemsasthefocusintheconstructionprocessofboredpiles.2preventionandcontrol2.1precisepositioning:spudforpreciselofting,linersembeddingposition,thestrictcontrolofnepositioningaccuracyofpile.Forpileverticaldegreeofcontrol,asaresultoflinersforthedrilldowndirectionhasaguidingrole,sotoprotectthecylinderupanddowntothevertical.Thefirstdrillholepositionandverticalitytogivespecialattentionto,todothis,mustuseupperandlowertwotic-tac-toeframe,atthesametimeintheprocessofdrillingshouldbethesettlementanddiscementobservationtform,atanytimetocorrect.Drillingisdevolvedreinforcingcage,tobereinforcingcagepositionaccuray,verticaldrop,coverthicknessmeetthedesignrequirements,usingwheeltypeconcreteblockisagoodwaytosolvethisproblem.Dealwithreinforcingcagehooksarefixedatthesametime,inordertosolvetheproblemofsteelreinmentcagefloating.2.StrictlycontroltheholebottomsedimentBecauseofdrilledpileallowablebearingcapacityandthecoefficientbym0valuerelationshipisgreat,clearbottombetterthanallowablebearingcapacityof3~4timesofpoor,soshouldstrictlydonotgreaterthanthethicknessofdesignrulesofdregdepositedatthebottomofthehole,toachievethis,holecleaningmustbethoroughly,adoptingtwotimesofblackhole(i.e.,loweringsteelreinmentcageandagainaftercatheterholecleaning),controltheslurryconcentration.Lastsedimentdetectionconcretepouringshouldtrytoshortenthetimeinterval,holecleaningagainifnecessary.Controlthesedimentthicknessforendbearingpilerock-socketedpileisparticularlyimportant,andmustbestrictlymeetthedesignrequirements,otherwisewillleadtounevensettlement,andendangerthesafetyoftheupperstructure.2.3keycontrolunderwaterconcretepouringprocess,ensurethequalityofpilebodyConstructionprocessofboredpilesoftheunderwaterconcreteperfusionislonger,hightechnicalrequirements,andalargeproportionofdrillingpilequalitycommonfault,areavailableonthislink,sostrictcontrolofunderwaterconcretepouringprocesstoensurethequalityofboredpileiscritical.Thespecificpracticesareasfollows:guaranteetheconcreteeffectivehead,intheprocessofunderwaterconcreteperfusion,funnelbottomholeshouldbehigherthanthatofWellswater4~6meters(whenthepileheadhighinthewaterhole,higherthanthatoffunnelbottomofpiletop4~6meters),especiallyinthelast10meters,concretecastingmustbestrictlycontrolledandmeetthetechniquerequirement,inordertosatisfythepipeinsideconcretespreadtotheoutsideofthetubeandthetubeoutsidethetopofthefirstconcretethesuperpressurerequired.shouldincreasethenumberofthefirstbucketofconcrete.Inpracticethenumberofthefirstbucketofconcreteshouldbeabletomakethecatheterembedmentdepthin1metersadvisable,ifbecauseofthedepthofembedmentistoosmall,canmaketheafterpouringtheconcreteisnottopofthewholelayerdownfirstpouringconcrete,butnearandsuccessivelyperfusionlayerbetweenclampsmudandbrokenpile.whenpouringunderwaterconcrete,afterthefirstbatchofperfusionconcreteshouldalwaysbeinthetopofeachbatchofconcretepouring,andcontactwithwaterormud,eafterpouringtheconcreteofthewaterprooflayer,toensurethequalityofafterpouringtheconcrete,andthereforerequiresthefirstconcretefromperfusiontoperfusioniscompleted,shouldalwayskeepthenecessarysticityandfluidity(aninitialsetting).Soyoumusttrytoshortenthefillingtime,maketheperfusionworktobedonebeforethefirstconcreteinitialsetting.Todothis,firstchoosecloseto,arelativelyflattransportroutes.Toconnectdifferentoperatingprocedures,tolargepilediameteranddepthoflongpile,heprocessofconcretepouring,oftenshoulddetectthedepthoftheconcretesurfaceandthebottomofthecatheter,keepthecatheterintheconcreteembedmentdepthismorethan2metres,otherwise,thenewconcretemaybreakthroughthefirstconcreteperfusion,taketotheconcrete,theconcreteandthesludgebywashingaroundintothepile,andformasandwich,brokenpile.Ofcourse,inordertopreventthetubeconcreteascensionisdifficult,evencan'tpullitout,causeaccidentburiedpipes,catheterumembedmentdepthshouldnotbegreaterthan6meters.underwaterconcreteshallbecontinuouscasting,forbiddeninterliningandfault.,ofcourse,maybeunexpectedemergenciesinconstructionprocess,suchassuddenblackouts,machinemalfunction,theconcretepouringbreakaccident.Atthispointintheverylikelyinterliningandbrokenpile,shouldactivelytakemeasurestoavoidloss.Ifyouneedtocastcanbetakentouseaircompressortoholecleaning,cleanthesedimentandtheupperlooseconcreteinhole,thenpouring,aftershoulddetecttheintegrityofthewholerootpile,toensurethequalityofcasting.concretepouringheightshouldbehigherthanactualdesignelevationabove50cm,shouldstepupthefinalpouringtyatthesametime,maketheholeofalllaitanceoverflow,ensurethecompactnessofconcretepilehead.7)rock-socketedpilessocketeddepthmustreachthedesigndepth,forthis,thesupervisionmustbestrictlycontrolledintheconstruction.Practicecanuserigidrodoraheavyhammerlineandcombinedwiththegeologicalreportforsure.Requirements,suchasdesignofstratathathavetotakethestonesamplesforidentification,todeterminewhethertoreachthedesignrequirementsoftherockface.Rock-socketedpilesuchasdesignofpilestrengthwhenwehaverequirementsforshallowcover(especiallythepierconstructionofpileatthesametimeintheexposedarea),shouldbecontrolledsteellinersoftheembedmentdepth,steellinerswiththetillthebottomofthehole.3BoredpilesusedasthefoundationofthelargestructuressuchasBridges,docks,soitsqualitymatter,itisrelatedtonationalandpeople'slifeandpropertysafety.Thispapermentionedbeforeafewbridgeinexpertevaluationthroughthequalitycheckandaccept.Soweshouldaccumulateexperienceinactualengineering,improvethetechnology,strengthenthecontrol,umlimittopreventqualityaccidents. 要:结合钻孔灌注桩实际施工中容易出现的质量问题,提出了相应的防治措施,论述了灌注桩的施工质量控制要点。:钻孔灌注桩;施工;质量。号:TU753.1节,相应容易产生的质量通病有:偏位、沉渣超厚、混凝土离析、桩身混凝22.12.2严格控制沉渣厚度m0值关系极大,清底较好的可比差的提高容许承载力3～4倍,所以应严格做到沉渣厚度不大于设计规定,要达到这一点,清孔必须彻底,采用两次清孔(即下放钢筋笼及导管后再次进行清孔),控2.34～64～610126浇注,过后应检测其整根桩的完,以保证浇注质量的优良。50有要求时,(特别是码头施工中对于覆盖较浅同时处于无遮掩海域的桩),应控3[12]Longandlight——《Bridgedesign&engineeringClosureofthemainspanontheSundoyaBridgeinNorwayisexpectedtotakeceinthefirstweekafterEaster.Thisgracefulcrossing,thesecondlongestofitstypeintheworld,isbeingbuiltinsituusinghighperformanceconcreteSundoyaBridgeissituatedinoneofNorway'smostscenicareas,only100kmsouthoftheArcticCircle.The538m-longbridgespansSundet,andwhenitiscompletewillprovideaferry-roadconnectionbetweenSundoyaandthe.Itislocatedsome35kmwestofthecityofMosjoen,closetohighway78betweenMosjoenandSandnessjoen.ItwillbethesecondlargebridgeprojectconnectingAlstenoyatothe,comingmorethan12yearsaftertheHelgelandBridgewasopened.Theregionisnostrangertoworld-recordscalebridges?theHelgelandBridge's425mlongmainspanwasthelongestcable-stayedspanintheworldwhenitopenedin1992.SundoyaBridgeisdividedintothreespans;ithasamainspanof298mandtwosidespansof120m.Themainspanwillbethesecondlongestspanintheworldforacontinuouspost-tensionedcastinceboxsectionconcretebridge.Intermsofitsdesign,consultantDrIngAas-JakobsenhasfollowedasimilarapproachtothattakenfortheRaftsundetBridge,openedin1998,towhichtheSundoyaBridgewillalmostbeatwin.Thetwobridgeshaveidenticalmainspans,butRaftsundethasfourspansasopposedtoSundoya'sthree.ContractorASAnlegg,whichispartofthejointventurebuildingSundoya,wasalsothecontractorontheRaftsundetBridge,andarchitectBoarchArkitekterhasalsoworkedonthetwoInJanuary2001thejointventureAFSundoybruawonthecontractfromStatensVegvesentobuildtheSundoyaBridge.ThisjointventureconsistedofthecontractorsReinerAnleggandNCCConstruction.Highperformanceconcreteiscentraltothedesignofthebridge?bothnormalweightHPCandlightweightHPC.Normalweightconcrete,atapproximay2500kg/m3,isusedforthe120msidespans,whilelightweightconcrete,whichweighsinatabout1970kg/m3,isusedforconstructionofthe298mmainspan.Thisenablesconstructiontoproceedusingthebalancedcantilevermethod.LocalrockfromNorwayisusedastheaggregateforthenormalweightconcrete,butthelightweightconcreterequiredanimportedsolution.NormallytheaggregateusedforlightweightconcreteinEuropeisexpandedclayorshale,butthismaterialhashighlevelsofabsorptionandforthisreason,regulationspreventsuchconcretefrombeingpumped.Inordertoaddressthis,thecontractoradoptedasimilarsolutiontothatusedonRaftsundetBridge?importingStaliteaggregatefromSouthCarolinaintheUSA.Staliteisproducedthroughthermalexpansionofhighqualityslate,andresultsinalightweightaggregatethatgivesconcreteofveryhighstrengthatlowunitweights.Itslowabsorptionofapproximay6%andhighparticlestrengtharetwoofthefactorsthatallowStalitetoachievehighstrengthconcreteinexcessof82.7MPa,themanufacturersays.Thebondandcompatibilityoftheaggregatewithcementpastereducemicro-crackingandenhancedurability,anditslowabsorptionmakesiteasytomixandpump.AccordingtoAFSundoybruaqualitymanagerJan-EirikNilsskog,thismaterialhasgivenaverygoodresult.Itproducesconcretethatiseasytopourintotheformworkanditgivesagoodsurfacefinish,hesays.Itisbeingpumpedsome120malongthebridgedecktotheconcretingposition.Concreteisproducedbya ntlocatedonly1kmfromthebridgesite.Constantmonitoringoftheconcreteweightisnecessarytoensurethatthecantileversareproperlybalanced.Thisistestedforeachpour.TheprojectbeganinJanuary2001atAkerVerdalwiththeproductionofcaissonsforthepierbases.InMay2001thetwocaissonsweretowed500kmnorthtothebridgesite.ThebridgeisbeingpouredinsituusingspecialconstructionequipmentdevelopedbyNRS.Thecycleforconstructionofeach5mwidebridgesegmentisaweek,andtwounitsarebeingusedontheSundoyaBridge.TheseparticularunitswerebuiltforASAnleggtouseontheVaroddenBridgeinKristiansandinNorway,andtheyhavealsobeenusedbythesamecontractorontheRafsundetBridge.ThedesignofthecentralpartofthemainspanofthebridgeisbasedontheuseoflightweightconcreteLC60whileotherpartsofthestructureusethemorestandardtypeC65.Becauseoftheaggressivemarineenvironment,thequalityoftheconcretemustbeparticularlygood.Thestructureisasinglecell,prestressedrectangularboxgirder,largelybuiltusingthetravellingformworksystemfromNRS.Theboxwidthis7manditsdepthvariesfrom3matthecentreofthespanto14.5moverthepiers.Closetotheabutments,concreteofqualityC25willbeusedinsidetheboxgirderasballast.Inaddition,thedesignershaveincludedthenecessaryelementsinsidetheboxgirderinordertoallowthepossibleadditionofpost-tensioningcablesinthefuture.Thelong-termbehaviourofsuchlargespansisnotfullyknown,sothepossibilitythatthemainspanmaysagovertimehastobetakenintoaccount.Thewidthoftheroadisaconstant7.5mfromthebarrierononesidetothatontheother,andthetotalwidthofthebridgeissome10.3m.Thereisa2mwidefootwayincludedinthewidthofthestructure.Thepiershaftisformedwithtwinlegs,whicharehollowinside.Thepiershaftsincorporatepermanentprestressingcablesandtheyhaveaconstantwallthicknessandawidththatvariesparabolicallyovertheirheight.Temporarytie-downpiersareusedtoconstructthebridge-theyarelocated35mintoeach120m-longsidespanfromthemainpiers.EachconsistsofanI-shapedshaft,whichistieddowntothegroundusingrockanchorsandconnectedtotheboxgirderbymeansofprestressingcables.Thepurposeofthesestructuralelementsistosupportthecantileverandpreventrotationinstrongwinds.Oncethebridgesuperstructureiscompleteandthemainpierprestressingisfullytensioned,thetemporarytie-downpierswillberemovedpiecebypiece.Thelocationofthebridge,onlyabout100kmsouthoftheArcticCircle,hasmeantthatspecialmeasureshavetobeintroducedtoallowconstructionworktocontinueallyearround.Apartfromtheobviousneedtoprovidesitelightingformuchofthewintertime,thechallengeofconcretingintemperatureswhichcanbeaslowas0Chastobe e.Hotconcreteisproducedforthebridge?sometimesupto30Candtheformworkhastobeinsulatedtokeeptheconcretewarm.ElectricheatingcablesarealsousedontheendofthepreviouspourtowarmuptheconcretebeforeConstructionofthenewbridgebeganinJanuary2000andisexpectedtobecompleteinSeptemberthisyear.TheconstructionofthecantileverstartedinsummerlastyearandisduetobefinishedinApril.When