chhavebeenwidelyusedtostrengthenconcretestructuresinrecentyears,aremanufacturedbypultrusioningeneral,withafibervolumeratioofabout.ThepropertiesoftworepresentativeproductsmadeinChinaandSwitzerlandrespectivelyarelistedinTable.Thestripscanbecurvedandcircumvolutedduetotheirsmallthickness.AtypicalCFRPstripwithpropertiessimilartothoseshowninTableisabletoresistatensileforceofkNormore,whiletheweightofamloanchortheFRPstripsatthecenteroftheweb.Asmall-scalemodelofasimpleFRPWWSisshowninFigure.TheFRPstripsareinitiallyprestressedtoalimitedextenttokeepthemstraightduring“weaving”.Then,theFRPwebistensionedbyadisplacementoftheinnerringbeamintheout-ofplanedirection,whichiseffectedeitherbyasetofprestressedtendonsorbysuspendingaheavymassfromtheinnerringbeam.Asaresult,atensionedFRPweb,whosegeometricstiffnessisabletoresistavarietyofloads,formsalarge-spanroofsystemwiththetworings.TheFRPWWSresemblesthecablenetstructureandthecable-membranestructure:theirmembersareflexible；andthegeometricstiffnessresultingfromtensionisutilizedtoresistloads.However,theFRPWWShasitsuniqueadvantages:()theFRPstripsareidealforsuperlarge-spanstructuresduetotheirlowself-weightandtheirsuperiormaterialpropertiesinthelengthwisedirection,whichareefficientlyutilized,whiletheweaknessofinferiorpropertiesinthetransversedirectionsisnotexposed；()significantdampingcanbeexpectedtoarisefromfrictionatjointsbetweenFRPstrips,whichcanenhancetheresistanceofthestructuretowindandearthquakeloads；()theregularweavingpatternleadstoanaestheticallypleasingsurface；and()thecorrosionresistanceofFRPandtheeaseofinstallationbecauseofitslightweighttranslateintolowmaintenancecosts.Inthispaper,thebasiclayoutandconstructionprocedureforasimpleFRPWWSsystemispresentedindetail.Theweavingpatternsinplanearesummarizedintothreetypes.SomespatialFRPWWSformsforpracticalapplicationsarealsoproposed.AsimplemechanicalmodelforindividualFRPstripsinthewebispresented.ResultsfromthefiniteelementanalysisofasimpleFRPWWSarealsodescribed.LAYOUTOFASIMPLEFRPWWSAsimpleFRPwovenwebstructureiscomposedofaFRPwovenweb,anouterringbeamandaninnerringbeamforanchorage,andanadditionalweightorasetofprestressedtendons,asshowninFigure.ThewebiswovenwithFRPstrips,andCFRPstripsorotherhigh-performancehybridFRPstripsaresuggested.CFRPstrips,whichhavebeenwidelyusedtostrengthenconcretestructuresinrecentyears,aremanufacturedbypultrusioningeneral,withafibervolumeratioofabout.ThepropertiesoftworepresentativeproductsmadeinChinaandSwitzerlandrespectivelyarelistedinTable.Thestripscanbecurvedandcircumvolutedduetotheirsmallthickness.AtypicalCFRPstripwithpropertiessimilartothoseshowninTableisabletoresistatensileforceofkNormore,whiletheweightofamlo。FRPWWS还能与其他种类结构综合使用形成混合结构体系。一个简单FRPWWS结构分析．单根FRP编织条如果忽略编织条相互接触处作用，每个编织条就主要受拉力作用。一个简单膜中呈一对编织条两端分别与内外环梁相接，如图所示。外环梁视作一不动点而内环梁视做一个刚体。编织条经历三种状态：初始施加预应力状态，外圈梁拉力状态和使用荷载时状态。假设编织带横截面积为A，弹性摸量为E，内外圈梁繁荣半径差为L，FRP编织条自重和柔度由于极小而忽略不计。如图（a）所示第一个状态中，对编织条初始水平预应力H。作用在编织条一端固EAH（）编织条初始长度LL（）如图（b）所示第二个状态中，内圈梁上作用有两个垂直力V使内圈梁下降从而拉伸编织条。编织条中拉力为T，其中水平分量为H,内圈梁位移为。根据平衡条件有VHT（）如果此时编织带应变为，则EAT（）LLL（）按照几何条件有LHV（）根据联立这些方程，,,T即可求得。在第三个状态中，编织条须承受一个活荷载q(x)，该荷载沿织条和内圈梁均布。在交汇处反作用力可被分解为水平作用力H和垂直方向反力R。距节点距离x处总偏离记为z（x），活荷载造成位移记作w（x），内环梁总位移记为。则有LVdxxqR)(()编织条弯曲形状由下式表示)(xqdxzdH()如果q(x)是均布荷载，曲线形状可以重积分简单算出。)()(LxxxLHqxz()则方程()变形为R=qL+V()编织条端点处坡度为HRdxdzx()HVdxdzLx()按照变形相容条件,第二状态下每个编织带总长度变化为dxLdxdzLs()但由应变求得在拉伸中伸长率为LEALHHs()因此,H和可通过式-求出。举例来讲,如图所示在FRPWWS中取一对编织条,其中L=m且材料性能与表一中产品那些性能相同。在第一个状态中，初始预应力为Mpa,则.，mL.,kNH。在第二个状态中，网轴垂直方向上竖向力V=kN。得出结果是m.，.，kNH.，编织条内应力为Mpa。最终，加上均布荷载q=.kN/m，因而m.，kNH.，编织条中最大应力为Mpa且作用在外沿连接点处。这个简单分析中，即可确定一个FRPWWS主要参数。这些包括最初控制拉力或称为预拉应力H,垂直方向力V或内环梁初位移。它们控制着荷载下织网变形和FRP条反力水平。．一个简单FRPWWS结构图所示FRPWWS结构是由ANSYS软件有限元分析法绘出。它具有m跨度且内环梁半径为m。表中产品取自这个结构设计，它具有MPa抗拉设计值。图中仅给出了放射线状部分。它其实共有套织条组构成，每组拥有三根编织条。因此，总共是根FRP条用于此结构。在有限元分析中考虑了大幅度变形几何非线性而忽略了织条间相互作用。FRP网自重仅为kN，比结构上所要承受荷载小多，因此可忽略。网膜上预施加预应力等级不超过Mpa，当内圈梁下坠后不超过MPa。经有限元法分析，在垂直力为kN第二阶段下，内圈梁向下位移.m，编织带最大应力为MPa。FRPWWS结构现在已经完工。其中每根编织条重量少于kg，一个成年人可轻易搬动，这个结构看上去很简单。FRPWWS条总质量估计为kg。完成后这个FRPWWS结构，由外环梁围绕整个区域受到一个.mkN设计均布荷载，包括屋面均布自重，风载和雪荷载。在这些荷载下，最大位移增幅。m，且FRP条总最大内力增加到MPa，大约是设计拉应力.。因此，这个建筑结构对承担这些荷载有足够强度。结论本文中介绍FRP织网结构（FRPWWS），其代表了FRP在大跨结构中一个新型应用。这种新结构关键环节如下：i.FRP网膜，环梁和纵向拉力系统是FRPWWS基本组成体系。ii.如图所示一个简单FRPWWS结构共有个施工步骤（图）。iii.平面网膜编排模式可分为三类：瓦片形式、辐射形式和多边形花纹结构。iv.同样基本原则下，可以有很多不同构造形式。本文讨论了多种不同可能形式，包括使用空间弧形外环梁，双网膜形式和多环梁形式。v.一个FRPWWS经历三个不同应力状态：初始预应力状态，纵向加载状态和工作荷载状态，三者都应在设计中加以考虑。致谢作者特此感谢中国自然科学基金会通过，国家重点工程FRP复合材料在土木上应用项目（项目号：）和香港澳门青年学者联合研究基金（项目号：）对本研究支持。anchortheFRPstripsatthecenteroftheweb.Asmall-scalemodelofasimpleFRPWWSisshowninFigure.TheFRPstripsareinitiallyprestressedtoalimitedextenttokeepthemstraightduring“weaving”.Then,theFRPwebistensionedbyadisplacementoftheinnerringbeamintheout-ofplanedirection,whichiseffectedeitherbyasetofprestressedtendonsorbysuspendingaheavymassfromtheinnerringbeam.Asaresult,atensionedFRPweb,whosegeometricstiffnessisaDevelopmentandanalysisofthelarge-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.INTRODUCTIONFRPisanewkindofstructuralmaterial,whoseuseincivilengineeringhasbeenactivelyexploredinrecentyears.Duetoitsfavorablepropertieslikecorrosionresistance,highstrength,lowweight,goodfatigueperformance,andlowmaintenancecost,itisconsideredtobeanidealmaterialforconstructinglong-spanstructuresinthenewcentury.However,itsmechanicalpropertiesaredistinctlydifferentfromthoseoftraditionalstructuralmaterialsinsomeaspects,suchasitsanisotropy.DuetotheuniquepropertiesofFRP,itisnecessarytoexplorenewformsoflarge-spanstructuresforitsefficientuseandforachievingspanslargerthanarepossiblewithtraditionalmaterials.Forexample,Maedaetal.()haveconceivedameter-spansuspensionbridgeusingFRP.TheFRPwovenwebstructure,anewlarge-spanstructuralsystem,ispresentedinthispaper.ThisnewsystemrepresentsanattemptaimedattheefficientutilizationoftheuniquecharacteristicsofFRPinalarge-spanroof.InanFRPWWS,thehighstrengthFRPstripsarewovenlikebamboostripsinaChinesebamboomattoformaplaneweb.Theouteredgeofthewebisanchoredonanouterringbeam,andaninnerringbeamisprovidedtoanchortheFRPstripsatthecenteroftheweb.Asmall-scalemodelofasimpleFRPWWSisshowninFigure.TheFRPstripsareinitiallyprestressedtoalimitedextenttokeepthemstraightduring“weaving”.Then,theFRPwebistensionedbyadisplacementoftheinnerringbeamintheout-ofplanedirection,whichiseffectedeitherbyasetofprestressedtendonsorbysuspendingaheavymassfromtheinnerringbeam.Asaresult,atensionedFRPweb,whosegeometricstiffnessisabletoresistavarietyofloads,formsalarge-spanroofsystemwiththetworings.TheFRPWWSresemblesthecablenetstructureandthecable-membranestructure:theirmembersareflexible；andthegeometricstiffnessresultingfromtensionisutilizedtoresistloads.However,theFRPWWShasitsuniqueadvantages:()theFRPstripsareidealforsuperlarge-spanstructuresduetotheirlowself-weightandtheirsuperiormaterialpropertiesinthelengthwisedirection,whichareefficientlyutilized,whiletheweaknessofinferiorpropertiesinthetransversedirectionsisnotexposed；()significantdampingcanbeexpectedtoarisefromfrictionatjointsbetweenFRPstrips,whichcanenhancetheresistanceofthestructuretowindandearthquakeloads；()theregularweavingpatternleadstoanaestheticallypleasingsurface；and()thecorrosionresistanceofFRPandtheeaseofinstallationbecauseofitslightweighttranslateintolowmaintenancecosts.Inthispaper,thebasiclayoutandconstructionprocedureforasimpleFRPWWSsystemispresentedindetail.Theweavingpatternsinplanearesummarizedintothreetypes.SomespatialFRPWWSformsforpracticalapplicationsarealsoproposed.AsimplemechanicalmodelforindividualFRPstripsinthewebispresented.ResultsfromthefiniteelementanalysisofasimpleFRPWWSarealsodescribed.LAYOUTOFASIMPLEFRPW        1Developmentandanalysisofthelarge-spanFRPwovenwebstructureABSTRACT:Aninnovativelarge-spanstructuralsystem,namelytheFRPwovenwebstructure(FRPWWS),isintroducedinthispaper.InanFRPWWS,thehigh-strengthFRPstripsare“woven”likebamboostripsinaChinesebamboomattoformaplaneweb.Theouteredgeofthewebisanchoredonanouterringbeam,andaninnerringbeamisprovidedtoanchorthe

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