中国土木工程结构控制的发展(翻译原文)

ADVANCESINSTRUCTURALCONTROLINCIVILENGINEERINGINCHINAABSTRACTINTHERECENTYEARS,MUCHATTENTIONHASBEENPAIDTOTHERESEARCHANDDEVELOPMENTOFSTRUCTURALCONTROLTECHNIQUESWITHPARTICULAREMPHASISONALLEVIATIONOFWINDANDSEISMICRESPONSESOFBUILDINGSANDBRIDGESINCHINASTRUCTURALCONTROLINCIVILENGINEERINGHASBEENDEVELOPEDFROMTHECONCEPTINTOAWORKABLETECHNOLOGYANDAPPLIEDINTOPRACTICALENGINEERINGSTRUCTURESTHEAIMOFTHISPAPERISTOREVIEWASTATEOFTHEARTOFRESEARCHESANDAPPLICATIONSOFSTRUCTURALCONTROLINCIVILENGINEERINGINCHINAITINCLUDESTHEPASSIVECONTROL,ACTIVECONTROL,HYBRIDCONTROLANDSEMIACTIVECONTROLFINALLY,THEPOSSIBLEFUTUREDIRECTIONSOFSTRUCTURALCONTROLINCIVILENGINEERINGINCHINAAREPRESENTEDKEYWORDSSTRUCTURALCONTROLBASEISOLATIONDAMPERINTRODUCTIONCIVILENGINEERINGSTRUCTURESLOCATEDINENVIRONMENTSWHEREEARTHQUAKESORLARGEWINDFORCESARECOMMONWILLBESUBJECTEDTOSERIOUSVIBRATIONSDURINGTHEIRLIFETIMETHESEVIBRATIONSCANRANGEFROMHARMLESSTOSEVEREWITHTHELATERRESULTINGINSERIOUSSTRUCTURALDAMAGEANDPOTENTIALSTRUCTURALFAILURETHETRADITIONALMETHODOFANTISEISMICTECHNIQUEISTOINCREASETHESTIFFNESSOFSTRUCTURESBYENLARGINGTHESECTIONOFCOLUMNS,BEAMS,SHEARWALLS,OROTHERELEMENTS,WHICHWILLENHANCETHESEISMICLOADBECAUSEOFTHEADDEDMASSTOSTRUCTURESASARESULT,ALTHOUGHTHECOSTOFSTRUCTURESWITHTRADITIONALANTISEISMICTECHNIQUEISINCREASEDALOT,THESAFETYLEVELOFSTRUCTURESISLESSIMPROVEDANOTHERDISADVANTAGEOFTHETRADITIONALANTISEISMICTECHNIQUEISTHATITFOCUSESONTHEPROTECTIONOFTHESTRUCTUREBUTNEGLECTSTHEFACILITIESINSIDETHESTRUCTUREHENCE,ITCANNOTBEUSEDINSOMESTRUCTURESWHOSEFACILITIESINSIDETHEMAREVERYIMPORTANT,SUCHASHOSPITALS,CITYLIFELINEENGINEERING,NUCLEARPLANTS,MUSEUMBUILDINGS,ANDTHEBUILDINGSWITHPRECISEINSTRUMENTSEVENTHOUGHENGINEERSCANNOTDESIGNABUILDINGWHICHISADAMAGEPROOFDURINGEARTHQUAKESANDSTRONGWINDS,THESTRUCTURALCONTROLISPROMISINGINREDUCINGTHEVIBRATIONOFSTRUCTURESDIERENTFROMTHETRADITIONALANTISEISMICMETHOD,THESTRUCTURALCONTROLTECHNIQUESUPPRESSESTHESTRUCTURALVIBRATIONBYINSTALLINGSOMEDEVICES,MECHANISMS,SUBSTRUCTURESINTHESTRUCTURETOCHANGEORADJUSTTHEDYNAMICPERFORMANCEOFTHESTRUCTURETHESTRUCTURALCONTROLSYSTEMISCOMMONLYCLASSIEDBYITSDEVICETYPERESULTINGINFOURGENERALCONTROLTYPESPASSIVE,ACTIVE,HYBRID,ANDSEMIACTIVECONTROLANACTIVECONTROLSYSTEMISTHEONEINWHICHANEXTERNALSOURCEPOWERCONTROLACTUATORSAPPLYFORCESTOTHESTRUCTUREINAPRESCRIBEDMANNERINCLUDINGACTIVETENDONSYSTEMATSANDACTIVEMASSDAMPERAMDAPASSIVECONTROLSYSTEMDOESNOTREQUIREANEXTERNALPOWERSOURCE,SUCHASBASEISOLATIONMETHOD,ENERGYDISSIPATIONDEVICES,TUNEDMASSDAMPERTMD,ANDTUNEDLIQUIDDAMPERTLDTHEHYBRIDCONTROLIMPLIESTHECOMBINEDUSEOFACTIVEANDPASSIVECONTROLSYSTEMSSEMIACTIVECONTROLSYSTEMSAREACLASSOFACTIVESYSTEMSINWHICHONLYSMALLMAGNITUDEOFEXTERNALENERGYISNEEDEDTOCHANGETHEPARAMETERSOFCONTROLSYSTEM,SUCHASACTIVEVARIABLESTINESSAVSSYSTEMANDACTIVEVARIABLEDAMPERAVDSYSTEMINTHERECENTYEARS,SERIOUSEORTSHAVEBEENUNDERTAKENINSTRUCTURALCONTROLANDFRUITFULACHIEVEMENTSHAVEBEENMADEINCHINASTRUCTURALCONTROLHASBEENDEVELOPEDFROMTHEORETICALANALYSISANDEXPERIMENTALRESEARCHINTOENGINEERINGAPPLICATIONSASETOFTECHNIQUESINCLUDINGBASEISOLATION,ENERGYDISSIPATION,TUNEDMASSDAMPERS,TUNEDLIQUIDDAMPERS,ACTIVEANDSEMIACTIVECONTROLMETHODSHAVEBEENUSEDINNEWLYBUILTSTRUCTURESOREXISTINGBUILDINGS,BRIDGES,FACILITIES,ANDOTHERSTRUCTURESINCHINAINTHISPAPER,THESTATEOFARTOFVIBRATIONCONTROLTECHNIQUES,INCLUDINGTHEORETICALANDEXPERIMENTALSTUDIES,PRACTICESINCIVILENGINEERINGAREREVIEWEDTHEPOSSIBLEFUTUREDIRECTIONSOFSTRUCTURALCONTROLINCIVILENGINEERINGISDISCUSSED2PASSIVECONTROL21BASEISOLATIONTHEBASEISOLATIONSYSTEMWASDEVELOPEDASONEOFREMARKABLETECHNOLOGIESTOREDUCETHESEISMICLOADOFBUILDINGANDEQUIPMENTTHEREAREVEKINDSOFMATERIALSTHATHAVEBEENUSEDFORISOLATORSINCHINA,INCLUDINGSANDLAYER,GRAPHITELIMEMORTARLAYER,SLIDEFRICTIONLAYER,ROLLERANDRUBBERBEARINGTHERUBBERBEARINGISTHEONEUSEDMOSTLYINCHINARELATIVELYEASYTOBEMANUFACTURED,ISOLATIONBEARINGSAREMADEBYVULCANIZATIONBONDINGOFSHEETSOFTHERUBBERTOTHINSTEELREINFORCINGPLATESTHEBEARINGSAREVERYSTIINTHEVERTICALDIRECTION,WHILEQUITEEXIBLEINTHEHORIZONTALDIRECTIONUNDERTHEEXCITATIONOFHORIZONTALEARTHQUAKES,THEFUNDAMENTALVIBRATIONPERIODOFANISOLATEDSTRUCTURECANBESHIFTEDFROMASHORTPERIODRANGETOALONGPERIODRANGETHUS,THEHORIZONTALSEISMICRESPONSEOFTHEISOLATEDSTRUCTUREISSIGNICANTLYLESSTHANTHEUNISOLATEDSTRUCTURETHESIGNICANTADVANTAGESOFSTRUCTURESWITHRUBBERBEARINGISOLATORSARESUMMARIZEDASFOLLOW1THEISOLATEDSTRUCTURESARESAFERINSTRONGEARTHQUAKETHEISOLATORSAREVERYEECTIVETOREDUCETHESEISMICRESPONSEOFSTRUCTURESANDCANPREVENTTHESTRUCTURESFROMDAMAGEORCOLLAPSECOMPAREDTOTHETRADITIONALANTISEISMICSTRUCTURES,THERESPONSESOFISOLATEDSTRUCTURESCANBEREDUCEDTO1/21/8OFTHEONEOFTRADITIONALSTRUCTURES,ACCORDINGTOTHETESTINGRESULTSANDTHERECORDSINREALEARTHQUAKE2THEBUILDINGCOSTOFISOLATIONSTRUCTURESCANBESAVED315OFTHECOSTOFTHEGENERALBUILDINGSACCORDINGTOTHENALSTATISTICSRESULTSOF30BUILDINGSWITHRUBBERBEARINGSCOMPLETEDINSOUTHERN,WESTERN,ANDNORTHERNCHINA3THESEISMICISOLATIONRUBBERBEARINGSYSTEMHASWIDERANGESOFAPPLICATION,BOTHINNEWLYDESIGNEDSTRUCTURESANDEXISTINGSTRUCTURES,IMPORTANTBUILDINGSANDCIVILBUILDINGSESPECIALLYFORHOUSEBUILDINGS,FORPROTECTINGTHEBUILDINGSTRUCTURES,ANDFORPROTECTINGTHEFACILITIESINSIDETHEBUILDING4THESAFELYWORKINGLIFEOFRUBBERBEARINGSISOVER70100YEARSACCORDINGTOTHEPERMANENTTESTINGANDINVESTIGATION,WHICHISLARGERTHANTHEWORKINGLIFEOFSTRUCTUREITSELFINORDERTOSOLVESOMEPROBLEMSFORMOREWIDEAPPLICATIONOFISOLATIONSYSTEMS,AGREATNUMBEROFTESTSFORRUBBERBEARINGSANDSHAKINGTABLETESTSFORBUILDINGMODELSWERECARRIEDOUTBYZHOUANDXIANTHETESTOFMECHANICALCHARACTERISTICSFORISOLATORSINCLUDESTHECOMPRESSIONTESTS,COMPRESSIONWITHSHEARCYCLELOADINGTESTSTHETESTOFDURABILITYFORISOLATORSINCLUDESLOWCYCLEFATIGUETESTS,CREEPTESTS,ANDOZONEAGINGTESTSTHETESTOFSTRUCTURALSYSTEMINCLUDESSHAKINGTABLETESTSFORLARGESCALESTRUCTURALMODELTHEREAREVEKINDSOFLOCATIONSOFLAYERWITHRUBBERBEARINGSINCHINAISOLATIONLAYERISLOCATEDONTHEBASEOFBUILDING,WHICHISTHEMOSTCOMMONMETHODTHEISOLATIONLAYERCANBELOCATEDONTHECERTAINSTORYOFTHEBASEMENT,WHICHISUSEDINMANYSTRUCTURESASSHOWNINFIGURE1ATHEISOLATIONCANALSOBELOCATEDONTHETOPOFTHERSTSTORYFIGURE1BORCERTAINSTORYOFSUPERSTRUCTUREFIGURE1CTHEISOLATIONLAYERLOCATEDONTHETOPOFTHEBUILDINGFIGURE1DISALWAYSUSEDTOADD12STORIESONTHETOPOFEXISTEDBUILDINGFORSEISMICRETROTISOLATIONLAYERLOCATEDATTHEJOINTSBETWEENSKYWALKANDBUILDINGSFIGURE1EISUSEDTOSEPARATETHEDIERENTMODESHAPESOFBUILDINGSCONNECTEDBYSKYWALKINTHECASEOFASEISMICISOLATEDBUILDINGWITHALARGEHEIGHTTOWIDTHRATIOHWR,THEOVERTURNINGMOMENTATTHELEVELOFSEISMICISOLATEDLAYERMAYEXCEEDTHEOVERTURNINGRESISTANCESUPPLIEDBYTHEGRAVITY,WHICHWILLRESULTINTHEDISCONNECTIONOFBEARINGSFROMTHESUPERSTRUCTUREANDPRODUCEANINTERNALDAMAGESOFRUBBERLAYERS,EVENLEADTOADESTROYOFTHEENTIREBUILDINGTHELIMITSOFTHEHWRFORISOLATEDBUILDINGWITHTHELAMINATEDRUBBERBEARINGSUNDERDIERENTCONDITIONSSUBJECTEDTOEARTHQUAKEEXCITATIONSWEREINVESTIGATEDBYLIANDWU4ACCORDINGTOTHENUMERICALRESULTS,ITHASBEENFOUNDTHATTHEEECTSOFSITESOILCONDITIONSONTHEHWRLIMITVALUESAREVERYIMPORTANT,INWHICHTHESOFTERTHESITEIS,THESMALLERTHEHWRLIMITVALUEISUNDERDIERENTSEISMICINTENSITIESTHEPREDOMINANTPERIODOFISOLATEDBUILDINGALSOPLAYSACONSIDERABLEROLEINTHEHWRLIMITVALUENAMELY,THEISOLATEDBUILDINGWITHALONGERPERIODMAYHAVEARELATIVELYLARGEHWRVALUETHESTINESSOFSUPERSTRUCTUREHASLITTLEEECTSONTHEHWRLIMITVALUEMOSTSTRUCTURESARESIMPLIEDASPLANARMODELSINBASEISOLATIONDESIGNHOWEVER,ALOTOFSTRUCTURESAREECCENTRICDUETOPLANIRREGULARITY,MASSECCENTRICITY,ELEVATIONIRREGULARITY,ANDSOFORTHTHEEARTHQUAKEISESSENTIALLYMULTIDIMENSIONALANDSOISTHESTRUCTURALRESPONSEEXCITEDBYEARTHQUAKE,WHICHWILLRESULTINTHETORSIONALLYCOUPLEDVIBRATIONTHATCANNOTBENEGLECTEDBASEDONMANYNUMERICALANALYSESONDIERENTSOILSITESDURINGTHEACTIONOFEARTHQUAKES,SIMPLIEDFORMULATEOFTORSIONALSEISMICACTIONSFORBASEISOLATEDECCENTRICSTRUCTURESISPRESENTED5ITISSHOWNTHATTHEPROPOSEDFORMULATIONSHAVEGOODACCURACYCOMPAREDWITHOTHERSITPROVIDESACONVENIENTANDSIMPLIEDMETHODFORTHESTRUCTURALDESIGNOFBASEISOLATEDECCENTRICBUILDINGSWITHRUBBERPADSDESIGNPRINCIPLESOFBASEISOLATIONANDENERGYDISSIPATIONSYSTEMSAREALSOINCLUDEDINCHINESECODEFORSEISMICDESIGNOFBUILDINGSPUBLISHEDBYTHEAGENCYOFMINISTRYOFCONSTRUCTIONIN2001THEDESIGNCODESFORBASEISOLATEDHIGHWAYBRIDGESANDBASEISOLATEDRAILWAYBRIDGESWEREALSOPUBLISHEDBYTHEAGENCIESOFMINISTRYOFTRANSPORTATIONANDMINISTRYOFRAILWAYCURRENTLY,THEREARETHREEDIERENTSETSOFTECHNICALCODESONSEISMICISOLATIONINCHINA31TECHNICALSPECICATIONFORSEISMICISOLATIONWITHLAMINATEDRUBBERBEARINGISOLATORSCECS1262001THISISTHENATIONALCODEFORDESIGNANDCONSTRUCTIONOFBUILDINGSANDBRIDGESWITHSEISMICISOLATIONINCHINA2STANDARDOFLAMINATEDRUBBERISOLATORSJB1182000THISISTHENATIONALSTANDARDOFISOLATORSFORLAMINATEDRUBBERBEARINGINCHINA3SEISMICISOLATIONANDENERGYDISSIPATIONFORBUILDINGDESIGNCHAPTER12INTHECODEFORSEISMICDESIGNOFBUILDINGS,GB500112001THISISAPARTOFNATIONALCODEINCHINAFORSEISMICDESIGNOFBUILDINGSSOMEMAININTRODUCTIONSFORALLTHESETHREECODESSTANDARDSONSEISMICISOLATIONINCHINAAREDESCRIBEDASBELOW31PROVIDETHEDESIGNMETHODSOFSEISMICISOLATIONFORBUILDINGS,BRIDGES,SPECIALSTRUCTURES,ANDINDUSTRYFACILITIES2PROVIDETHEDESIGNMETHODSOFSEISMICISOLATIONFORNEWSTRUCTURESANDTHERETROTOFEXISTEDSTRUCTURES3ALLOWTOFOLLOWTHREEDESIGNLEVELSDEPENDINGONTHEIMPORTANCEOFSTRUCTURESANDREQUIREMENTSOFOWNERSINTHEAREASWITHDIERENTECONOMICSITUATIONINCHINALEVEL1,FORGENERALSTRUCTURES,USINGISOLATIONWILLSAVEBUILDINGCOSTABOUT315LEVEL2,FORIMPORTANTSTRUCTURES,USINGISOLATIONWILLINCREASEBUILDINGCOST3FORESPECIALLYIMPORTANTSTRUCTURES,USINGISOLATIONWILLINCREASEBUILDINGCOST57BUTTHEISOLATIONBUILDINGSDESIGNEDBYANYLEVELWILLINCREASETHESEISMICSAFETYABOUT28TIMESCOMPAREDWITHTHETRADITIONALANTISEISMICBUILDING4PROVIDETWOMETHODSOFSTRUCTURALANALYSISFORSEISMICISOLATIONOFSTRUCTURES,EQUIVALENTSHEARMETHOD,ANDTIMEHISTORYANALYSISTHEEQUIVALENTSHEARMETHODISACHIEVEDBYSTATICANALYSISANDONLYAPPLICABLEFORSTRUCTURESWITHHEIGHTLESSTHAN40MOR10STORIES,REGULARCONGURATION,ANDPREDOMINANTSHEARDEFORMATIONSWHEREAS,THETIMEHISTORYANALYSISCANBEUSEDFORALLKINDSOFSTRUCTURES5ALLOWREDUCINGTHESEISMICSHEARFORCEFORDESIGNINGSUPERSTRUCTURE,WHICHCANSAVETHEBUILDINGCOSTOFGENERALCIVILBUILDINGS,ESPECIALLYINSOMEPOORECONOMICAREASTHERSTMULTISTORYHOUSEBUILDINGWITHRUBBERBEARINGINCHINAWASCOMPLETEDIN1993,ASSHOWNINFIGURE23ITISAN8STORYBUILDINGSUPPORTEDBY23RUBBERBEARINGSWITHDIERENTDIAMETERSFROM60CMTO80CMTHESTRUCTUREHASUNDERGONETWOSTRONGEARTHQUAKESIN1994AND1996ANDISSTILLEMPLOYEDNOWWITHOUTANYDAMAGETHEISOLATEDBUILDINGSWITHTHELARGESTAREAINTHEWORLDARENAMEDISOLATIONHOUSEBUILDINGSONSUBWAYHUBIHBSHASSHOWNINFIGURE3,WHICHISLOCATEDNEARLYTHECENTEROFBEIJING3THEREISAVERYLARGEPLATFORMCOMPOSEDBYANRCFRAMEWITHTWOSORTIES,WHICHISUSEDTOPUTALLEQUIPMENTANDFACILITIESFORRAILWAYHUBINITANDCOVERTHENOISEFROMRAILWAYHUBTRAINSTHESIZEOFPLATFORMIS1500MWIDEAND2000MLONGTHEREARE50HOUSEBUILDINGSBUILTONTHETOPOOROFTHEPLATFORMTHEOORAREAOFALLISOLATIONHOUSEBUILDINGSISAPPROXIMATELY480000MWHICHISTHELARGESTAREAUSINGSEISMICISOLATIONINTHEWORLDTHERUBBERBEARINGLAYERISLOCATEDONTHETOPOOROFTHEPLATFORM,ASSHOWNINFIGURE4THEGREATBENETSAREACHIEVEDBYUSINGSTORYISOLATIONFORTHISBUILDINGCOMPLEXINCLUDINGINCREASINGTHESAFETYOFSTRUCTURESTO4TIMESOFTRADITIONALDESIGNSCHEMES,SAVING25OFTHECONSTRUCTIONCOST,RAISINGTHENUMBEROFSTORIESFROM6TO9,ANDSOLVINGTHEENVIRONMENTALPROBLEMSOFRAILWAYVIBRATIONANDNOISEINTHECITYCENTERTHEAPPLICATIONOFSEISMICISOLATORSINCHINAHASPROVEDTHATTHEISOLATIONSYSTEMISMORESAFE,ECONOMIC,ANDREASONABLETHANTHETRADITIONALSTRUCTURALSYSTEMMORETHAN500FULLSCALEIMPLEMENTATIONSOFBASEISOLATEDBUILDINGSANDBRIDGESHAVEBEENACCOMPLISHEDTOALLEVIATETHEEARTHQUAKEANDTRACINDUCEDRESPONSESOFAR622ENERGYDISSIPATIONANENERGYDISSIPATIONSYSTEMISFORMEDBYADDINGSOMEENERGYDISSIPATERSINTOTHESTRUCTURETHEENERGYDISSIPATERSPROVIDETHESTRUCTUREWITHLARGEAMOUNTSOFDAMPINGWHICHWILLDISSIPATEMOSTVIBRATIONENERGYFROMVIBRATIONSOURCESANDENSURETHESAFETYOFSTRUCTURESINEARTHQUAKEORTHECOMFORTLEVELINWINDMANYKINDSOFDAMPERS,INCLUDINGFRICTIONDAMPERS,VISCOELASTICDAMPERS,VISCOUSUIDDAMPERS,LEADDAMPERSANDMETALLICDAMPERSHAVEBEENDEVELOPEDINCHINA2AOUTSIDEVIEWBSECTIONALVIEWCDETAILSOFRUBBERBEARINGFIGURE2THERSTMULTISTORYHOUSEBUILDINGWITHRUBBERBEARINGINCHINAFIGURE3FRONTELEVATIONOFIHBSHFRICTIONPROVIDESANEXCELLENTMECHANISMOFENERGYDISSIPATIONANDHASBEENUSEDFORMANYYEARSINAUTOMOTIVEBRAKESTODISSIPATEKINETICENERGYOFMOTIONTHISKINDOFDAMPERSAREMADEOFORDINARYMATERIALSWITHSIMPLEMECHANICALCONGURATIONSHENCETHEYAREAPPLICABLEFORMULTISTORYANDHIGHRISEBUILDINGSTHEBEHAVIORSOFTWODIERENTENERGYDISSIPATIONDAMPERSBASEDONFRICTIONASSHOWNINFIGURE5WERESTUDIEDBYZHOUANDLIU7THERESULTSSHOWEDTHATTHEFRICTIONENERGYDISSIPATIONDAMPERSCANDISSIPATEAGREATDEALOFEARTHQUAKEINPUTENERGYANDTHEHYSTERETICBEHAVIORISSTABLETOSATISFYTHEENERGYDISSIPATIONREQUIREMENTSFOREARTHQUAKEINDIERENTSEISMICINTENSITIESOFCHINA,DOUBLEPHASEFRICTIONDAMPERSWEREPROPOSEDBYZHANGANDYANG8THEEXPERIMENTALRESULTSSHOWEDTHATTHEPROPOSEDDOUBLEPHASEFRICTIONDAMPERCANREDUCETHESTRUCTURALVIBRATIONBOTHINSMALLANDSTRONGEARTHQUAKEWUANDOU9PRESENTEDAKINDOFPSEUDOFRICTIONDAMPERTOREDUCETHEEECTSOFADDITIONALSTINESSINPALLFRICTIONDAMPERSBASEDONTHEGEOMETRYNONLINEARITYOFFOURLINKMECHANISMOFPALLTYPEDFRICTIONDAMPER,THEINUENCEOFFRAMEDISPLACEMENT,BRACESTINESS,DAMPERSLIPFORCEOFANOVELPSEUDOVISCOUSFRICTIONALDAMPERASSHOWNINFIGURE6,ISANALYZEDBYWUETAL10THERESULTSSHOWEDTHATTHENOVELFRICTIONALDAMPERHASGREATHYSTERETICCHARACTERISTICSWITHREMARKABLYSMALLERTENSIONFORCEOFBRACETHANTHATOFPALLTYPEDFRICTIONDAMPER,WHICHISBENECIALFORFRAMECOLUMNSTOIMPROVEITSDUCTILITYADAMPERWITHINNOVATIVECOMPOSITEFRICTIONMATERIALHASBEENDEVELOPEDBYXIANETAL11AFULLSCALETESTOFTHISINNOVATIVEFRICTIONDAMPERANDTHESHAKINGTABLETESTFORSTRUCTURALMODELWITHTHEDAMPERWEREIMPLEMENTED,WHICHSHOWEDTHATTHESEISMICRESPONSESOFSTRUCTURESWITHDAMPERSCANBEREDUCED3040THEFRICTIONDAMPERSHAVEBEENAPPLIEDINENGINEERINGSTRUCTURESINCHINAFOREXAMPLE,134PASSIVEFRICTIONDAMPERSWITH100KNTO200KNSLIDINGFORCECAPACITYHAVEBEENIMPLEMENTEDINSHENYANGGOVERNMENTOCEBUILDINGSIN1997TORETROTTHISBUILDING,ASSHOWNINFIGURE7THEPSEUDODYNAMICTESTSOFA1/3SCALEMODELOFTHEBUILDINGWITHANDWITHOUTFRICTIONDAMPERSWERECARRIEDOUTTOEXAMINETHESEISMICCAPACITYOFTHERETROTTEDBUILDINGS12LEADDAMPERSHAVEIDEALELASTICPLASTICPROPERTYWITHRECTANGULARHYSTERESISCURVETHEYIELDINGLIMITOFLEADDAMPERSCANNOTBEADJUSTEDAFTERDESIGNEDHENCE,INASTRONGEARTHQUAKE,THEENERGYDISSIPATIONCAPACITYOFDAMPERSWILLBELOWBECAUSEOFLARGEDEFORMATIONWHEREAS,INAMILDEARTHQUAKE,THEDAMPERSCANNOTYIELDTODISSIPATEENERGYINNOVATIVEBENDSHEARANDSHEARTYPELEADDAMPERSWHICHCANATTENUATETHEVIBRATIONOFBUILDINGSBOTHINMILDANDSTRONGEARTHQUAKESWEREDEVELOPEDBYZHOUETAL13VISCOELASTICDAMPERSHAVETHEMERITSOFDISSIPATINGENERGYATALLDEFORMATIONLEVELSTHEREFOREVISCOELASTICDAMPERSCANBEAPPLIEDINBOTHWINDANDSEISMICPROTECTIONSOMECOMMERCIALPRODUCTSOFVISCOELASTICDAMPERSINCHINAARESHOWNINFIGURE8THEMECHANICALMODEL,DESIGNTECHNIQUE,ANDOPTIMUMMETHODFORVISCOELASTICDAMPERSHAVEBEENDEVELOPEDINCHINA14,15VISCOELASTICDAMPERSWEREALSOAPPLIEDTOENGINEERINGSTRUCTURESFORSUPPRESSINGTHESTRUCTURALVIBRATIONCAUSEDBYWINDOREARTHQUAKEINCHINA,SUCHASSUQIANCOMMUNICATIONBUILDINGFIGURE9ANDCHAOSHANXINHEBUILDINGFIGURE10FLUIDSCANALSOBEUSEDTODISSIPATEENERGYHENCEMANYKINDSOFVISCOUSUIDDAMPERSHAVEBEENPROPOSEDCOMMERCIALVISCOUSUIDDAMPERSWITHDIFFERENTCAPACITIESWEREALSOAVAILABLEINCHINAFIGURE11VISCOUSDAMPERSHAVEBEENUSEDINSOMEENGINEERINGSTRUCTURESINCHINA,INCLUDINGBEIJINGYINGTAICENTER,YIZHENYUANBUILDINGOFHUAIYINCITY,BEIJINGEXHIBITIONBUILDING,ANOFFICEBUILDINGOFSUQIANCITY,CONSTRUCTIONBUILDINGOFSUQIANCITY,ANOFFICEBUILDINGOFXIANCITY,ANDBEIJINGRESTAURANTTHECENTRETOWERBUILDINGOFBEIJINGYINTAICENTERISA60STORYSTEELSTRUCTUREWITH248MINHEIGHTANDSUSCEPTIBLETOWIND,SO73SETSOFVISCOUSUIDDAMPERSWEREINSTALLEDINITFIGURE1216METALLICDAMPERSDISSIPATEENERGYINPUTTOASTRUCTUREFROMANEARTHQUAKETHROUGHINELASTICDEFORMATIONOFMETALSBASEDONTHEEXPERIMENTALSTUDYANDTHEORETICALANALYSISOFTHEFATIGUEPROPERTIESOFXSHAPESTEELPLATEENERGYDISSIPATERS,THENONLINEARMETHODOFSTEELPLATEOFTHEENERGYDISSIPATERWASESTABLISHEDANDTHESTRAINFATIGUEPARAMETERSAREDETERMINED,WHICHPROVIDEANIMPORTANTBASEFORTHEDESIGNOFMILDSTEELENERGYDISSIPATERS19INMOSTCASES,METALLICDAMPERSDISSIPATEENERGYTHROUGHTHENONLINEARPROPERTYOFSTEELPLATEAFTERYIELDINGOUTOFPLANEDUALFUNCTIONALMILDSTEELDAMPERSAREPRESENTEDBYGLIANDHLI20,ASSHOWNINFIGURES13AND14,WHICHISTOSTRENGTHENTHEINITIALSTINESSBYEXTENDINGTHESTEELPLATEINITSOWNPLANEANDTOINCREASETHEENERGYDISSIPATINGABILITYBYCHANGINGTHEGEOMETRICSHAPEOFTHESTEELPLATERESULTSFROMTHEORETICALANALYSISANDQUASISTATICEXPERIMENTSSHOWEDTHATTHESETYPESOFMILDMETALLICDAMPERSNOTONLYPROVIDECERTAINSTINESSINNORMALUSE,BUTALSOAREOFGOODABILITYOFTHESEISMICENERGYDISSIPATIONDUALFUNCTIONALMILDMETALLICDAMPERSHAVEBEENINSTALLEDINNO3EXPERIMENTBUILDINGOFDALIANUNIVERSITYOFTECHNOLOGYDUTINCHINATOINCREASETHESTINESSOFTHERSTOORANDSUPPRESSTHEEARTHQUAKEINDUCEDVIBRATION21,ASSHOWNINFIGURE15FORSOMEOLDDESIGNEDBUILDINGSBASEDONTHEDATEDBUILDINGDESIGNCODESINWHICHTHESEISMICPROTECTIONWASSELDOMTAKENINTOACCOUNTBOTHTHELANDDEVELOPERSANDENGINEERSHAVETODETERMINEWHETHERTODEMOLISHTHEMANDTHENSETUPNEWONESORREUSETHEORIGINALBUILDINGSTHROUGHMAKINGSOMEINNOVATIONSTOMEETTHECURRENTNEEDDUETOECONOMY,MANYOLDEXISTINGBUILDINGSHAVEBEENINCREASEDWITHNEWSTORIESONTHETOPOFTHEMINCHINAANEWTYPEOFENERGYDISSIPATEDSTRUCTURALSYSTEMFORTHEEXISTINGBUILDINGWITHTHESTORYINCREASEDFRAMEWASPRESENTED22,INWHICHTHESLIDINGFRICTIONLAYERBETWEENTHELOWESTINCREASEDOOROFOUTERFRAMESTRUCTUREANDROOFOFORIGINALBUILDINGWASAPPLIED,ANDENERGYDISSIPATEDDAMPERSWEREUSEDFORTHECONNECTIONSBETWEENTHECOLUMNSOFOUTERFRAMEANDEACHOOROFORIGINALBUILDING,ASSHOWNINFIGURE16THEEXPERIMENTALRESULTSSHOWEDTHATFRICTIONANDENERGYDISSIPATEDDEVICESAREVERYEECTIVEINREDUCINGTHESEISMICRESPONSEANDDISSIPATINGTHEINPUTENERGYOFMODELSTRUCTUREAFOURSTORYOCEBUILDING,BUILTUPIN1950SWITHOUTTHESEISMICDESIGNALONGBEILINGSTREETINSHENYANGCITYOFCHINABECAUSETHEREWASNOANYSEISMICCODESATTHATTIMEINCHINA,WASDESIGNEDANDANALYZEDWITHANINCREASEDFOURSTORYOUTERFRAMESTRUCTUREONITSTOPBYUSINGTHEPASSIVECONTROLMETHODPRESENTEDTHEEXISTINGBUILDINGISCOMPOSEDOFBRICKMASONRYSTRUCTUREITSDESIGNISNOTINCOMPLIANCEWITHTHECURRENTSEISMICCODEOFCHINATHESEISMICPROTECTIONINTENSITYONTHISBUILDINGSITEISVIIDEGREE,ANDTHESITESOILBELONGSTOTHETYPEIIINCHINESECODETHEPRACTICALBUILDINGSTORYINCREASEDSTRUCTUREAFTERCONSTRUCTIONISSHOWNINFIGURE17THERESULTSSHOWEDTHATTHEGOODSEISMICREDUCTIONEECTIVENESSONDISPLACEMENTSANDACCELERATIONSCANBEACHIEVEDBYINSTALLINGTHEFRICTIONANDENERGYDISSIPATEDDEVICESINTHESTORYINCREASEDSTRUCTURESFIGU