建筑畢業(yè)設(shè)計(jì)外文翻譯及譯文--大跨度FRP網(wǎng)架結(jié)構(gòu)的展望和分析.doc

中國石油大學(xué)（華東）本科畢業(yè)設(shè)計(jì)（論文）1Developmentandanalysisofthelarge-spanFRPwovenwebstructureABSTRACT:Aninnovativelarge-spanstructuralsystem,namelytheFRPwovenwebstructure(FRPWWS),isintroducedinthispaper.InanFRPWWS,thehigh-strengthFRPstripsare“woven”likebamboostripsinaChinesebamboomattoformaplaneweb.Theouteredgeofthewebisanchoredonanouterringbeam,andaninnerringbeamisprovidedtoanchortheFRPstripsatthecenteroftheweb.Thestiffnessofthewebtoresistvariousloadsisderivedfromtheinitialprestressingduringthe“weaving”stageandtheadditionaltensioningasaresultoftheout-of-planemovementoftheinnerringbeam.Asaresultofthehighstrength-toweightratioofFRP,thisnewstructuralformoffersanattractiveoptionfortheconstructionofspatialstructureswithspanslongerthanarepossiblewithconventionalstructuralmaterials.Inthispaper,thebasiclayoutandconstructionprocedureforasimpleFRPWWSisfirstpresented.Threebasicweavingpatternsarenextexplained.Severalvariationsofthebasicstructuralsystemarealsoproposed.AsimplemechanicalmodelispresentedforthedeformationofindividualFRPstrips.Resultsfromafiniteelementanalysisofanexamplestructurearealsogiven.TheresultsoftheseanalysesconfirmthefeasibilityoftheFRPWWS.1INTRODUCTIONFRPisanewkindofstructuralmaterial,whoseuseincivilengineeringhasbeenactivelyexploredinrecentyears.Duetoitsfavorablepropertieslike中國石油大學(xué)（華東）本科畢業(yè)設(shè)計(jì)（論文）2corrosionresistance,highstrength,lowweight,goodfatigueperformance,andlowmaintenancecost,itisconsideredtobeanidealmaterialforconstructinglong-spanstructuresinthenewcentury.However,itsmechanicalpropertiesaredistinctlydifferentfromthoseoftraditionalstructuralmaterialsinsomeaspects,suchasitsanisotropy.DuetotheuniquepropertiesofFRP,itisnecessarytoexplorenewformsoflarge-spanstructuresforitsefficientuseandforachievingspanslargerthanarepossiblewithtraditionalmaterials.Forexample,Maedaetal.(2002)haveconceiveda5000meter-spansuspensionbridgeusingFRP.TheFRPwovenwebstructure,anewlarge-spanstructuralsystem,ispresentedinthispaper.ThisnewsystemrepresentsanattemptaimedattheefficientutilizationoftheuniquecharacteristicsofFRPinalarge-spanroof.InanFRPWWS,thehighstrengthFRPstripsarewovenlikebamboostripsinaChinesebamboomattoformaplaneweb.Theouteredgeofthewebisanchoredonanouterringbeam,andaninnerringbeamisprovidedtoanchortheFRPstripsatthecenteroftheweb.Asmall-scalemodelofasimpleFRPWWSisshowninFigure1.TheFRPstripsareinitiallyprestressedtoalimitedextenttokeepthemstraightduring“weaving”.Then,theFRPwebistensionedbyadisplacementoftheinnerringbeamintheout-ofplanedirection,whichiseffectedeitherbyasetofprestressedtendonsorbysuspendingaheavymassfromtheinnerringbeam.Asaresult,atensionedFRPweb,whosegeometricstiffnessisabletoresistavarietyofloads,formsalarge-spanroofsystemwiththetworings.TheFRPWWSresemblesthecablenetstructureandthecable-membranestructure:theirmembersareflexible；andthegeometricstiffnessresultingfrom中國石油大學(xué)（華東）本科畢業(yè)設(shè)計(jì)（論文）3tensionisutilizedtoresistloads.However,theFRPWWShasitsuniqueadvantages:(1)theFRPstripsareidealforsuperlarge-spanstructuresduetotheirlowself-weightandtheirsuperiormaterialpropertiesinthelengthwisedirection,whichareefficientlyutilized,whiletheweaknessofinferiorpropertiesinthetransversedirectionsisnotexposed；(2)significantdampingcanbeexpectedtoarisefromfrictionatjointsbetweenFRPstrips,whichcanenhancetheresistanceofthestructuretowindandearthquakeloads；(3)theregularweavingpatternleadstoanaestheticallypleasingsurface；and(4)thecorrosionresistanceofFRPandtheeaseofinstallationbecauseofitslightweighttranslateintolowmaintenancecosts.Inthispaper,thebasiclayoutandconstructionprocedureforasimpleFRPWWSsystemispresentedindetail.Theweavingpatternsinplanearesummarizedintothreetypes.SomespatialFRPWWSformsforpracticalapplicationsarealsoproposed.AsimplemechanicalmodelforindividualFRPstripsinthewebispresented.ResultsfromthefiniteelementanalysisofasimpleFRPWWSarealsodescribed.2LAYOUTOFASIMPLEFRPWWSAsimpleFRPwovenwebstructureiscomposedofaFRPwovenweb,anouterringbeamandaninnerringbeamforanchorage,andanadditionalweightorasetofprestressedtendons,asshowninFigure1.ThewebiswovenwithFRPstrips,andCFRPstripsorotherhigh-performancehybridFRPstripsaresuggested.CFRPstrips,whichhave中國石油大學(xué)（華東）本科畢業(yè)設(shè)計(jì)（論文）4beenwidelyusedtostrengthenconcretestructuresinrecentyears,aremanufacturedbypultrusioningeneral,withafibervolumeratioofabout65%.ThepropertiesoftworepresentativeproductsmadeinChinaandSwitzerlandrespectivelyarelistedinTable1.Thestripscanbecurvedandcircumvolutedduetotheirsmallthickness.AtypicalCFRPstripwithpropertiessimilartothoseshowninTable1isabletoresistatensileforceof400kNormore,whiletheweightofa300mlongstripislessthan70kg.Incomparison,theselfweightofa300mlonghighstrengthsteelcablewhichcanresistthesameloadismorethan500kg.Thestripsarearrangedintoaplanesurfaceofasuitablepatternbysomepre-definedrules.Inthesimplestweavingpattern,eachstrippassesoveronecrossingstripandunderthenexttoformaweblikeawovenfabric.ApartofsuchwebisshowninFigure2(Pongetal.2004).Inamoregeneralcase,thenumberofstripsmeetingatajointandtheanglesbetweenthesestripsarethebasicparametersofaweavingpattern:twostripsat90toeachotherareshowninFig.3(a),threestripsat60showninFig.3(b),andfourstripsat45showninFig.3(c).Atthejoints,stripscanbefullyinter-connectedbyadhesivebondingafterc