土木毕业设计外文翻译原文翻译桥梁

1、外文文件原文ThebridgecrackproducedthereasontosimplyanalyseInrecentyears,thetrafficcapitalconstructionofourprovincegetsswiftandviolentdevelopment,allpartshavebuiltalargenumberofconcretebridges.Inthecourseofbuildingandusinginthebridge,relevanttoinfluenceprojectqualityleadofcommonoccurrencereportthatbridgeco

2、llapseevenbecausethecrackappearsTheconcretecanbesaidtooftenhaveillnesscomingonwhilefracturingandfrequently-occurringdisease,oftenperplexbridgeengineersandtechnicians.Infact,iftakecertaindesignandconstructionmeasure,alotofcrackscanbeovercomeandcontrolled.Forstrengthenunderstandingofconcretebridgecrac

3、kfurther,isitpreventprojectfromendangerlargercracktotryonesbest,thistextmakeanmoreoverallanalysis,summarytoconcretekindandreasonofproduction,bridgeofcrackasmuchaspossible,inordertodesign,constructandfindoutthefeasiblemethodwhichcontrolthecrack,gettheresultoftakingprecautionsagainstYuWeiRan.Concreteb

4、ridgecrackkind,origincauseofformationInfact,theorigincauseofformationoftheconcretestructurecrackiscomplicatedandvarious,evenmanykindsoffactorsinfluenceeachother,buteverycrackhasitsoneorseveralkindsofmainreasonsproduced.Thekindoftheconcretebridgecrack,onitsreasontoproduce,canroughlydivideseveralkinds

5、asfollows:(1)loadthecrackcausedConcreteinroutinequiet.Isitloadtomoveandcrackthatproduceclaimtoloadthecrackunderthetimesofstressbridge,summinguphasdirectstresscracks,twokindsstresscrackoncesmainly.Directstresscrackrefertooutsideloaddirectcrackthatstressproducethatcause.Thereasonwhythecrackproducesisa

6、sfollows,1,Designthestageofcalculating,doesnotcalculateorleaksandcalculatespartlywhilecalculatinginstructure;Calculatethemodelisunreasonable;Thestructureissupposedandaccordedwithbystrengthactuallybystrength;Loadandcalculateorleakandcalculatefew;Internalforceandmatchingthemistakeincomputationofmuscle

7、;Safetycoefficientofstructureisnotenough.Donotconsiderthepossibilitythatconstructatthetimeofthestructuraldesign;Itisinsufficienttodesignthesection;Itissimplylittleandassigningthemistakeforreinforcingbartosetup;Structurerigidityisinsufficient;Constructanddealwithimproperly;Thedesigndrawingcannotbeexp

8、lainedclearlyetc.2,Constructionstage,doesnotpileupandconstructthemachines,materiallimiting;Isitprefabricatestructurestructurereceivestrengthcharacteristic,standup,isithang,transport,installtogetupatwilltounderstand;Constructnotaccordingtothedesigndrawing,altertheconstructionorderofthestructurewithou

9、tauthorization,changethestructureandreceivethestrengthmode;Donotdothetiredintensitycheckingcomputationsundermachinevibrationandwaittothestructure.3,Usingstage,theheavy-dutyvehiclewhichgoesbeyondthedesignloadpassesthebridge;Receivethecontact,strikingofthevehicle,shipping;Strongwind,heavysnow,earthqua

10、kehappen,explodeetc.Stresscrackoncemeansthestressofsecondarycausedbyloadingoutsideproducesthecrack.Thereasonwhythecrackproducesisasfollows,1,Indesignoutsideloadfunction,becauseactualworkingstateandroutine,structureofthingcalculatehavediscrepancyorisitconsidertocalculate,thuscausestressoncetocausethe

11、structuretofractureinsomeposition.TwoisitjoinbridgearchfootisitisitassignXshapereinforcingbar,cutdownthisplaceway,sectionofsizedesignandcutwithscissorsatthesametimetoadoptoftentodesigntocutwithscissors,theorycalculateplacethiscanstorecurvedsquarein,butrealityshouldisitcanresistcurvedstilltocutwithsc

12、issors,sothatpresentthecrackandcausethereinforcingbarcorrosion.2,Bridgestructureisitdigtrough,turnonhole,setupoxleg,etc.toneedoften,difficulttouseaaccurateonediagrammatictoisitisitcalculatetoimitatetogoonincalculatinginroutine,setupandreceivethestrengthreinforcingbaringeneralfoundationexperience.Stu

13、dieshaveshown,afterbeingdugtheholebythestrengthcomponent,itwillproducethediffractionphenomenonthatstrengthflows,intensiveneartheholeinautensil,producedtheenormousstresstoconcentrate.Inlongtostepprestressingforceofthecontinuousroofbeam,oftenblockthesteelbunchaccordingtotheneedsofsectioninternalforcei

14、nstepping,setuptheanchorhead,butcanoftenseethecrackintheanchorfirmsectionadjacentplace.Soifdealwithimproper,incornerorcomponentformsuddenchangeoffice,blockplacetobeeasytoappearcrackstrengthreinforcingbarofstructurethe.Intheactualproject,stresscrackonceproducedthemostcommonreasonwhichloadsthecrack.St

15、resscrackoncebelongtoonemorepieceofnatureofdrawing,splittingoff,shearing.Stresscrackonceisloadedandcaused,onlyseldomcalculateaccordingtotheroutinetoo,butwithmoderntocalculateconstantperfectionofmeans,timesofstresscracktocanaccomplishreasonablecheckingcomputationstoo.Forexampletosuchstresses2timesofp

16、roducingasprestressingforce,creeping,etc.,departmentsfiniteelementprocedurecalculateslevelspolecorrectlynow,butmoredifficult40yearsago.Inthedesign,shouldpayattentiontoavoidingstructuresuddenchange(orsectionsuddenchange),whenitisunabletoavoid,shoulddopartdealwith,cornerforinstance,makeroundhorn,sudde

17、nchangeofficemakeintothegradationzonetransition,isitisitmixmuscletoconstructtostrengthenatthesametime,cornermixagainobliquetoreinforcingbar,astolargeholeinautensilcansetupprotectingintheperimeteratthetermsofhavinganglesteel.Loadthecrackcharacteristicinaccordancewithloadingdifferentlyandpresentingdif

18、ferentcharacteristicsdifferently.Thecrackappearpersonwhodrawmore,thecuttingareaortheseriouspositionofvibration.Mustpointout,isitgetupcoverorhavealongkeepintoshortcrackofdirectiontoappearpersonwhopress,oftenthestructurereachesthesignofbearingtheweightofstrengthlimit,itisanomenthatthestructureisdestro

19、yed,itsreasonisoftenthatsectionalsizeispartialandsmall.Receivethestrengthwaydifferentlyaccordingtothestructure,thecrackcharacteristicproducedisasfollows:1,Thecentreisdrawn.Thecrackrunsthroughthecomponentcrosssection,theintervalisequalonthewhole,andisperpendiculartoreceivingthestrengthdirection.While

20、adoptingthewhorlreinforcingbar,lieinthesecond-classcracknearthereinforcingbarbetweenthecracks.2,Thecentreispressed.Itisparallelontheshortanddenseparallelcrackwhichreceivethestrengthdirectiontoappearalongthecomponent.3,Receivecurved.Mostnearthelargesectionfromborderisitappearanddrawintodirectionverti

21、calcracktobeginpersonwhodrawcurvedsquare,anddeveloptowardneutralizationaxlegradually.Whileadoptingthewhorlreinforcingbar,canseeshortersecond-classcrackamongthecracks.Whenthestructurematchesmusclesless,therearefewbutwidecracks,fragilitydestructionmaytakeplaceinthestructure4,Pressedbigandpartial.Heavy

22、topressandmixpersonwhodrawmusclealessonelighttopigeonholeintothecomponentwhilebeingpartialwhilebeingpartial,similartoreceivingthecurvedcomponent.5,Pressedsmallandpartial.Smalltopressandmixpersonwhodrawmuscleamoreoneheavytopigeonholeintothecomponentwhilebeingpartialwhilebeingpartial,similartothecentr

23、eandpressedthecomponent.6,Cut.Pressobliqulywhenthehoopmuscleistoodenseanddestroy,theobliquecrackwhichisgreaterthan45?directionappearsalongthebellyofroofbeamend;Isitisitisitdestroytopresstocuttohappenwhenthehoopmuscleisproper,underpartisitinvite45?directionparallelobliquecrackeachothertoappearalongro

24、ofbeamend.7,Sprained.Componentonesidebellyappearmanydirectionobliquecrack,45?oftreaty,first,andtolaunchwithspiraldirectionbeingadjoint.8,Washedandcut.4sideisitinvite45?directioninclinedplanedrawandsplittotakeplacealongcolumncapboard,formthetangentplaneofwashing.9,Someandispressed.Sometoappearpersonw

25、hopressdirectionroughlyparallellargeshortcrackswithpressure.(2)crackcausedintemperaturechangeTheconcretehasnatureofexpandingwithheatandcontractwithcold,lookonastheexternalenvironmentconditionorthestructuretemperaturechanges,concretetakeplaceoutofshape,ifoutofshapetorestrainfrom,producethestressinthe

26、structure,producethetemperaturecrackpromptlywhenexceedingconcretetensilestrengthinstress.Insomebeingheavytostepfoot-pathamongthebridge,temperaturestresscanisitgobeyondlivingyearstresseventoreach.Thetemperaturecrackdistinguishesthemaincharacteristicofothercrackswillbevariedwithtemperatureandexpandedo

27、rclosedup.Themainfactorisasfollows,tocausetemperatureandchange1,Annualdifferenceintemperature.Temperatureischangingconstantlyinfourseasonsinoneyear,butchangerelativelyslowly,theimpactonstructureofthebridgeismainlytheverticaldisplacementwhichcausesthebridge,canpropupseatmoveorsetupflexiblemound,etc.n

28、ottoconstructmeasurecoordinate,throughbridgefloorexpansionjointgenerally,cancausetemperaturecrackonlywhenthedisplacementofthestructureislimited,forexamplearchedbridge,justbridgeetc.TheannualdifferenceintemperatureofourcountrygenerallychangestherangewiththeconductoftheaveragetemperatureinthemoonofJan

29、uaryandJuly.Consideringthecreepcharacteristicoftheconcrete,theelasticmouldamountofconcreteshouldbeconsideredrollingoverandreducingwhentheinternalforceoftheannualdifferenceintemperatureiscalculated.2,Rizhao.Afterbeingtannedbythesunbythesuntothesideofbridgepanel,thegirderorthepier,temperatureisobvious

30、lyhigherthanotherposition,thetemperaturegradientispresentedanddistributedbythelineshape.Becauseofrestrainoneselffunction,causepartdrawstresstoberelativelyheavy,thecrackappears.Rizhaoandfollowingtoisitcausestructurecommonreasonmost,temperatureofcracktolowerthetemperaturesuddenly3,Lowerthetemperatures

31、uddenly.Fallheavyrain,coldairattack,sunset,etc.cancausestructuresurfacetemperaturesuddenlydroppedsuddenly,butbecauseinsidetemperaturechangerelativelyslowproducingtemperaturegradient.Rizhaoandlowerthetemperatureinternalforcecanadoptdesignspecificationorconsultrealbridgematerialsgoonwhencalculatingsud

32、denly,concreteelasticmouldamountdoesnotconsiderconvertingintoandreducing4,Heatofhydration.Appearinthecourseofconstructing,thelargevolumeconcrete(thicknessexceeds2.0),afterbuildingbecausecementwatersendoutheat,causeinsideverymuchhightemperature,theinternalandexternaldifferenceintemperatureistoolarge,

33、causethesurfacetoappearinthecrack.Shouldaccordingtoactualconditionsinconstructing,isitchooseheatofhydrationlowcementvarietytotryonesbest,limitcementunitsconsumption,reducetheaggregateandenterthetemperatureofthemould,reducetheinternalandexternaldifferenceintemperature,andlowerthetemperatureslowly,can

34、adoptthecirculationcoolingsystemtocarryontheinsidetodispeltheheatincaseofnecessity,oradoptthethinlayerandbuilditinsuccessioninordertoacceleratedispellingtheheat.5,Theconstructionmeasureisimproperatthetimeofsteammaintenanceorthewinterconstruction,theconcreteissuddenandcoldandsuddenandhot,internalande

35、xternaltemperatureisuneven,apttoappearinthecrack.6,PrefabricateTroofbeamhorizontalbafflewhentheinstallation,propupseatburystencilplatewithtransferflatstencilplatewhenweldinginadvance,ifweldmeasuretobeimproper,ironpiecesofnearbyconcreteeasytoisitfracturetoburn.Adoptelectricheatpiecedrawlawpiecedrawpr

36、estressingforceatthecomponent,prestressingforcesteeltemperaturecanriseto350degreesCentigrade,theconcretecomponentisapttofracture.Experimentalstudyindicates,arecausedtheintensityofconcretethatthehightemperatureburnstoobviouslyreducewithrisingoftemperaturebysuchreasonsasthefire,etc.,glueingformingthed

37、eclinethereuponofstrengthofreinforcingbarandconcrete,tensilestrengthdropby50%afterconcretetemperaturereaches300degreesCentigrade,compressionstrengthdropsby60%,glueingthestrengthofformingtodropby80%ofonlyroundreinforcingbarandconcrete;Becauseheat,concretebodydissociateinkevaporateandcanproduceandshri

38、nksharplyinalargeamount(3)shrinkthecrackcausedIntheactualproject,itisthemostcommonbecauseconcreteshrinksthecrackcaused.Shrinkkindinconcrete,plasticityshrinkisititshrinks(isitcontracttodo)tobethemainreasonthatthevolumeofconcreteoutofshapehappenstoshrink,shrinkspontaneouslyinofconstructing,concretehap

39、pens,thecementwaterresponseisfierceatthismoment,thestrandtakesshapegradually,secretewaterandmoisturetoevaporatesharply,theconcretedesiccatesandshrinks,itisatthesametimeconductoneselfwithdignitynotsinkingbecauseaggregate,sowhenhardenconcreteyet,itcallplasticityshrink.Theplasticityshrinkproducingamoun

40、tgradeisverybig,canbeuptoabout1%.Ifstoppedbythereinforcingbarwhiletheaggregatesinks,formthecrackalongthereinforcingbardirection.Ifweb,roofbeamofTandroofbeamofcaseandcarrybaseplatehandoverofficeincomponentverticaltobecomesectionalplace,becausesinktooreallytosuperficialobeyingthewebdirectioncrackwillh

41、appenevenlybeforehardenning.Forreducingconcreteplasticityshrink,itshouldcontrolbywaterdustwhenbeingconstructthan,lastlong-timemixing,unloadingshouldnottooquick,isitisittakecloselyknittosmashtoshake,verticaltobecomesectionalplaceshoulddividelayerbuild.Shrinkandshrink(doandcontract).Aftertheconcreteis

42、formedhard,asthetoplayermoistureisevaporatedprogressively,thehumidityisreducedprogressively,thevolumeofconcreteisreduced,iscalledandshrunktoshrink(doandcontract).Becauseconcretetoplayermoisturelosssoon,itisslowforinsidetolose,producesurfaceshrinkheavy,insideshrinkalightoneeventoshrink,itisoutofshape

43、torestrainfrombytheinsideconcreteforsurfacetoshrink,causethesurfaceconcretetobearpullingforce,whenthesurfaceconcretebearspullingforcetoexceeditstensilestrength,produceandshrinkthecrack.Theconcretehardensafter-contractiontojustshrinkandshrinkmainly.Suchasmixmusclerateheavycomponent(exceed3%),betweenr

44、einforcingbarandmoreobviousrestraintsrelativelythatconcreteshrink,theconcretesurfaceisapttoappearinthefullofcrackscrackle.Shrinkspontaneously.Spontaneoustoitshrinkstobeconcreteinthecourseofhardenning,cementandwatertakeplaceinkreact,theshrinkwithhavenothingtodobyexternalhumidity,andcanpositive(whethe

45、rshrink,suchasordinaryportlandcementconcrete),cannegativetoo(whetherexpand,suchasconcrete,concreteofslagcementandcementofflyash).Thecharshrinks.Betweencarbondioxideandhyrateofcementofatmospheretakeplaceoutofshapeshrinkthatchemicalreactioncause.Thecharshrinksandcouldhappenonlyabout50%ofhumidity,andac

46、celeratewithincreaseofthedensityofthecarbondioxide.Thecharshrinksandseldomcalculates.Thecharacteristicthattheconcreteshrinksthecrackisthatthemajoritybelongstothesurfacecrack,thecrackisrelativelydetailedinwidth,andcriss-cross,becomethefullofcracksform,theformdoesnothaveanylaw.Studieshaveshown,influen

47、ceconcreteshrinkmainfactorofcrackasfollows,1,Varietyofcement,gradeandconsumption.Slagcement,quick-hardeningcement,low-heatcementconcretecontractivityarerelativelyhigh,ordinarycement,volcanicashcement,aluminacementconcretecontractivityarerelativelylow.Cementgradelowinaddition,unitvolumeconsumptionhea

48、vyrubingdetaileddegreeheavy,thentheconcreteshrinksthemoregreatly,andshrinktimeisthelonger.Forexample,inordertoimprovetheintensityoftheconcrete,oftenadoptandincreasethecementconsumptionmethodbyforcewhileconstructing,theresultshrinksthestresstoobviouslystrengthen.2,Varietyofaggregate.Suchabsorbingwate

49、rratesasthequartz,limestone,cloudrock,granite,feldspar,etc.aresmaller,contractivityisrelativelylowintheaggregate;Andsuchabsorbingwaterratesasthesandstone,slate,angleamphibolite,etc.aregreater,contractivityisrelativelyhigh.Aggregategrainsoffoot-pathheavytoshrinklightinaddition,watercontentbigtoshrink

50、thelarger.3,Watergraythan.Theheavierwaterconsumptionis,thehigherwateranddustare,theconcreteshrinksthemoregreatly.4,Mixthepharmaceuticaloutside.Itisthebettertomixpharmaceuticalwater-retainingpropertyoutside,thentheconcreteshrinksthesmaller.5,Maintainthemethod.Waterthatgoodmaintenancecanacceleratethec

51、oncretereacts,obtaintheintensityofhigherconcrete.Keephumidityhigh,lowmaintainingtimetobethelongertemperaturewhenmaintaining,thentheconcreteshrinksthesmaller.Steammaintainwaythanmaintainwayconcreteisittakelighttoshrinknaturall.6,Externalenvironment.Thehumidityislittle,theairdrying,temperaturearehigh,

52、thewindspeedislargeintheatmosphere,thentheconcretemoistureisevaporatedfast,theconcreteshrinksthefaster.7,Shakeandsmashthewayandtime.Machineryshakewayofsmashingthanmakefirmbyrammingortampingwayconcretecontractivitytakelittlebyhand.Shakingshoulddetermineaccordingtomechanicalperformancetosmashtime,areg

53、enerallysuitablefor55s/time.Itistooshort,shakeandcannotsmashcloselyknit,itisinsufficientornoteveninintensitytoformtheconcrete;Itistoolong,causeanddividestorey,thickaggregatesinkstothegroundfloor,theupperstratathatthedetailedaggregatestays,theintensityisnoteven,theupperstrataincidentshrinkthecrack.An

54、dshrinkthecrackcausedtotemperature,worthyofconstructingthereinforcingbaragainingcanobviouslyimprovetheresistingthesplittingofconcrete,structureofespeciallythinwall(thick200cmofwall).Mixmuscleshouldisitadoptlightdiameterreinforcingbar(8|?construct14|?)tohavepriority,littleintervalassign(whether10cons

55、truct15cm)onconstructing,thewholesectionisitmixmuscletoberateunsuitabletobelowerthan0toconstruct.3%,cangenerallyadopt0.3%0.5%.(4),crackthatcausesoutofshapeofplinthofthegroundBecausefoundationverticaltoeventosubsideorhorizontaldirectiondisplacement,makethestructureproducetheadditionalstress,gobeyondr

56、esistingtheabilityofdrawingofconcretestructure,causethestructuretofracture.Theevenmainreasonthatsubsideofthefoundationisasfollows,1,Reconnoitrestheprecisionandisnotenoughfor,testthematerialsinaccuratlyingeology.Designing,constructingwithoutfullygraspingthegeologicalsituation,thisisthemainreasonthatc

57、ausethegroundnottosubsideevenly.Suchashillsareaorbridge,districtofmountainridge,holeintervaltobetoofarwhenreconnoitring,andgroundriseandfallbigtherock,reconnoitringthereportcantfullyreflecttherealgeologicalsituation.2,Thegeologicaldifferenceofthegroundistoolarge.Buildingitinthebridgeofthevalleyofthe

58、ditchofmountainarea,geologyofthestreamplaceandplaceonthehillsidechangelarger,eventhereareweakgroundsinthestream,becausethesoilofthegrounddoesnotcausesanddoesnotsubsideevenlywiththecompressing.3,Thestructureloadsthedifferencetoobig.Undertheunanimousterms,wheneveryfoundationtooheavytoloaddifferenceing

59、eologicalsituation,maycauseevenlytosubside,forexamplehightofilloutsoilcaseshapeinthemiddlepartoftheculvertthantoisittakeheavytoloadbothsides,tosubsidesoonheavythanbothsidesmiddlepart,caseisitmightfracturetocontain4,Thedifferenceofbasictypeofstructureisgreat.Uniteitinthebridgethesamly,mixanduseanddoe

60、snotexpandthefoundationandafoundationwiththefoundation,oradoptafoundationwhenafoot-pathoralongdifferenceisgreatatthesametime,oradoptthefoundationofexpandingwhenbasiselevationiswidelydifferentatthesametime,maycausethegroundnottosubsideevenlytoo5,Foundationbuiltbystages.Inthenewly-builtbridgenearthefo