正在进行安全检测...
发布时间：2023-11-29 09:03:45 来源：文档文库
小
中
大
字号：
Afiniteelementmodelforindependentwireropecorewithdoublehelicalgeometrysubjectedtoaxialloads
CENGIZERDONMEZ1,∗andCERDEMIMRAK2
IstanbulTechnicalUniversity,InstituteofInformatics,ComputationalScienceandEngineeringProgram,34469Maslak,Istanbul,Turkey2IstanbulTechnicalUniversity,FacultyofMechanicalEngineering,34394Gumussuyu,Istanbul,Turkeye-mail:cerdonmez@gmail.com;imrak@itu.edu.tr
MSreceived27March2009;revised26March2010;accepted1June2010
Abstract.Duetothecomplexgeometryofwireswithinawirerope,itisdifficulttomodelandanalyseindependentwireropecoreaccurately(IWRC.Inthispaper,amorerealisticthree-dimensionalmodellingapproachandfiniteelementanalysisofwireropesareexplained.SinglehelicalgeometryisenoughtomodelsimplestraightstrandwhileIWRChasamorecomplexgeometrybyinclusionofdoublehelicalwiresinouterstrands.Takingtheadvantageofthedoublehelicalwires,three-dimensionalIWRCsmodellingisappliedforbothrightregularlayandlanglayIWRCs.Wire-bywirebasedresultsaregatheredbyusingtheproposedmodellingandanalysismethodundervariousloadingconditions.IllustrativeexamplesaregivenforthoseshowtheaccuracyandtherobustnessofthepresentFEanalysisschemewithconsideringfrictionalpropertiesandcontactinteractionsbetweenwires.FEanalysisresultsarecomparedwiththeanalyticalandavailabletestresultsandshowreasonableagreementwithasimplerandmorepracticalapproach.
Keywords.Wirestrand;independentwireropecore;doublehelices;wire-by-wireanalysis.
1.IntroductionOnthedesignofwireropes,asimplestraightstrandisusedasacorestrandanditiswoundbyouterstrandstocompletethewholegeometry.Independentwireropecore(IWRCisaspecialtypeofwirerope,whichcanbeusedinapplicationsandbecomesthecoreforsomeothertypesofropesknownasSealeIWRCorWarringtonIWRC.Largetensileforcestrengthofthewireropesisveryimportantinapplicationareaswhereinthesmallbendingandtorsionalstiffness.Ingeneral,twotypesoflayconstructionareusedinwireropestrands:regularlayandlanglay.Inregularlaywireropeconstructions,laydirectionsofthewireswithintheouterstrandareoppositeindirectiontothecorestrand.Inlanglaywireropeconstructions,ontheotherhand,thedirectionsofthewiresarethesameasthedirectionofthecorestrand.Underaxialloadingconditions,regularlaywireropestendtotightenupwhilelanglayropeshavethetendencytounwind;forthisreasonlanglayropesareusedonlywhen1
ropeendsarerestrainedfromrotating.WhenthewireropeisrununderlargelateralcompressiveloadsandwhenadditionalaxialloadingcapacityisrequiredIWRCsarepreferred(Velinsky1989.Wireropetheoryisbasedonawell-knownclassicaltreatiseonelasticitybyLove(1944andgeneralnonlinearequilibriumequationsarederivedandpresented.Itisfoundthatthefrictionlesstheoryiswidelyusedtosolveequilibriumequationsbecauseofthenonlinearbehaviourandthecomplexnatureofthewireropes.AlthoughconsiderableresearchstudieshavebeencarriedoutabouttheanalyticalsolutionsofIWRCsbyCostello&Sinha(1977,Costello(1990,Velinskyetal(1984,Velinsky(1985,Velinsky(1989,Jolicoeur&Cardou(1991,Elataetal(2004,Usabiaga&Pagalday(2008,alittleworkhasbeendoneusingthedoublehelicalgeometryandrealmodellingapproachesvianumericalanalysis.Alltheabove-mentionedanalyticalmodelstakesintoaccountasimplestraightstrandasbeingthemaincomponentformodellingIWRCandmorecomplexwireropesbyusingIWRC.AfrictionlesstheoryispresentedforthedeterminationofthestaticresponseofasimplestraightstrandinCostello&Sinha(1977whichwastheoneofthefirstanalyticalsolutionsusingthetheoryofLove(1944.Costello(1990hasalsopresentedthegeneralbehaviourofthewireropesindifferentaspectssuchasstaticresponseofreducedroperotation,simplifiedbendingtheoryforwirerope.AwireropewithcomplexcrosssectionsasaSealeIWRCisanalysedinamanner,whichwillpredicttheaxialstaticresponsebyVelinskyetal(1984.AgeneralnonlineartheorytoanalysecomplexwireropeisdevelopedasanextensionofthefrictionlessstrandtheoryofCostelloforaSealeIWRCbyVelinsky(1985.Wireropeswiththreetypesofcores:independentwireropecores(IWRC,fibre-core(FCandwirestrandcore(WSCareinvestigatedandVelinsky(1989developedadesignmethodologyformulti-laywirestrands.AnumberofanalyticalmodelsoftwistedwireropesunderaxisymmetricloadsarecomparedsimultaneouslywitheachotherandwiththetestresultsinJolicoeur&Cardou(1991.AmongthemPhillips&Costello’s(1985 