development of brd al prototyperbento/tmp/infrarisk-/summer... · 2018-07-18 · 0 7502 26405 39895...

ANALYSIS AND MITIGATION OF RISKS IN INFRASTRUCTURES | INFRARISK-!

Development of aluminium alloy hysteretic damping system for seismic retrofitting of pre-coded reinforced concrete buildings

Earthquake Engineering - Earthquakes and Tsunamis

Development of BRD_AL Prototype

Ricardo Sousa Alves Ferreira

Supervisors:

Professor Jorge Proença (PhD, Associate Professor IST, CERIS Senior Researcher)

Professor António Gago (PhD, Associate Professor IST, CERIS Senior Researcher)


Earthquake Engineering - Earthquakes and Tsunamis

Development of BRD_AL PrototypeOutline of the Doctoral Programme

Introduction:• Theproblem

• Objectives

AnoverviewoftheStateof

theart:• Hystereticyieldingdevices

• AluminiumAlloys

• BRD_ALprototype

Methodology:• Assessmentofaluminiumalloys

behaviour;

• Assessmentofdevicebehaviour

(localanalysis);

• Analysisofdevicebehaviour

(globalanalysis);

• CasestudyAnalysis


Quantification of RC buildings in Lisboa (INE Census 2011)

The problem - Seismic risk of pre-coded buildings

Regulatoryframework

Inexistent RSEP(1961) REBAP,RSAEP(1983)

Yearofconstruction

Until1919

1919-1945

1946-1960

1961-1970

1971-1980

1981-1990

1991-1995 1996-200 2001-

20052006-2011

NºofexistingRCbuildings 0 7502 26405 39895 61042 55562 24930 28317 29088 20237

Transitionperiod1958–Introductionof1st regulation

RSCCS

NºofexistingRCBuildingsdesignwithoutseismicprovisions:>26.000buildingsNºofexistingRCBuildingsdesignedwithoutdatedseismicprovisions:>100.000buildings

Estimate:


The problem - Pilotis Buildings

Constructionofseveralbuildingsduringthe50’sand60’s,withparticularcharacteristics:

• Commonlyusedinresidentialareas;

• Mainvolume+slendercolumnsintransitiontogroundlevel;

• Seismicbehaviourofthisbuildingtypology– occurrenceofsoft-storeyphenomena


The problem - Soft-storey phenomena

• Abruptstiffnesstransitionbetweenbuildingbodyandsupportingslendercolumns,resultinginsignificantoverstressontransitioncross-sectionsofthesupportingcolumns;

• PilotisbuildingsconstructedinLisbonduringthe50’sand60’softhelastcenturywherenotdesignedforseismicactionandarepronetothistypeofphenomenaincaseofamoderatetohighseismicevent.

Earthquake

Gravity

SoftstoreyfailuresinGolcuk,Turkey(IzmitandD�̈�zceearthquakes).Source(AIR)


The objective – Drift reduction D• ThereductionofdriftD canbeattainedby

theincreaseofstructuraldamping;

• Hystereticdampercanbeanefficientandeconomicalwaytoincreasedamping(x),enablingthestructuretocomplytoacertainlimitdamage(LD);

• Hystereticdamperstakeadvantageofthedeformationcapacityofmetallicelements,usuallysteel;

• Dampingprovidedbythedeviceisdeterminedbyitsdissipativecapacityineachcycle;

• ThehystereticbehaviourcontrolparametersareK1(initialstiffness),K2(post-yieldstiffness)andFy(yieldstrength).

Di

ADRSSpectrum

Df

Df Di


State of the Art – Dissipative devices – Brief overview

Classificationofdevices

DisplacementDependent

Linear(LD)

Non-Linear(NLD)/Hysteretic(HD)

Yieldingmetal(YMD)Friction(FD)

VelocityDependent/ViscousDampers(VD)

FluidViscous(FVD)

FluidSpring(FSD)

Accelerationdependent

ModifiedInput

CombinationSource:FredericoMazzolani,LuisCalado,Introductiontoreversiblemixedtechnologies,FP6PROHITECproject

HystereticbehaviourofBucklingRestrainedBraces- asaprincipleforthedevelopmentofnewdevice


State of the Art – Aluminium Alloys overviewClassificationofalloys

(AluminiumassociationandEN)

Constitutiveelements: Fabricationstage Heat-treatment

Series Alloyingelements

1xxx PureAluminium

2xxx Copper

3xxx Manganese

4xxx Silicon

5xxx Magnesium

6xxx Magnesiumandsilicon

7xxx Zinc

8xxx Otherelements

F- Rough;O-annealed;H – Work-hardened;W-Temperednonstabilizedstage;T-heattreated

• Heattreatablealloys;

• Notheattreatablealloys

StagesHandTcanalsobesubdividedintermsofthestabilizationstage,ageingprocessesandcoolingprocessesSource:Mazzolani,1995


State of the Art – Aluminium Alloys overview

Properties Aluminium Steel

Averageweightdensityg(kgm-3)

2700 7850

MeltingpointT(oC) 658 1450-1530

Linearthermalexpansion,a(oC-1)

24x10-6 12x10-6

Specificheat,C(calg-1) 0,255 0,12

Thermalconductivityl,(calcm-1 s-1 oC-1)

0,52 0,062

Electricalresistivityr(µW cm)

2,4 15,5

YoungModulus,E(Nmm-1) 70x103 210x103


State of the Art – Aluminium Alloys overview

MechanicalProperties Aluminium Steel

Yieldstressfy(Nmm-2)

50-360 235-350

Ultimatestressft(Nmm-2)

80-410 360-510

Ultimatestrainet(%)

10-25 25-30


State of the Art- Aluminium alloys overview

AluminiumAlloys(advantages):• Capabilityofproductionofelementswithnonconventionalcrosssectionsusing

alternativefabricationprocessessuchextrusionorEDM;

• Ductility;

• Aestheticappearance;

• Lowweight(about1/3oftheweightofsteel);

• Corrosionresistance;

• Lowmaintenance;

• Recyclable

Source:World-Aluminium.org


Development BRD_AL PrototypeRCStructure

Movementduetoseismicaction(driftD)

ElasticZone

Yieldingzone

Objectives:• Alternativetothedissipativebracing

deviceparadigm:useanextrudedaluminiumalloymemberwithoutinfill;

• Light-weightandeasytointegrateinbracingsystem;

• Devicethatissimpletointegratebothinnewandexistingbuildings

• Devicecapableofwithstandingsignificantplasticization,henceincreasingstructuraldampingduetohystereticbehaviourofthealuminiummember;

Compressiveaction


Development BRD_AL Prototype - Methodology

Tasks:

1. State-oftheartreview,PhDcurricularcourses,contactswithnationaland

Internationalpartnersforthedevelopmentofthedevice;

2. Definitionofthealuminiumalloy.

3. Crosssectionanalysis.

4. GlobalAnalysis;

5. Casestudyanalysis;

6. Writingofthethesis


Task 2 – Aluminium Alloy analysis Experimentalcampaignoftensionandcompressiontestswillbecarriedoutforthecharacterizationof3differentaluminiumalloys.

Apre-determinedsetofaluminiumalloys,basedintheEN1999referencealloys,willbechosenfortesting.Thechosenaluminiumalloysare:

• ENAW1050• ENAW5054T6• ENAW6061T6;

Standardstobeusedincompressionandtensionwillbe:

• EN10002-1– “Tensiletesting-Part1:Methodoftestatambienttemperature;

• ASTME9-“Standardcompressiontestingofmetallicmaterialsatroomtemperature”.

ThiswillallowtohaveaconsolidatedcomparisonframeworkwithtestalreadyperformedbyProf.Mazzolani;andthenormativevaluesprovidedintheEN1999-1(EC9)andwithanalyticaldefinitionsliketheRamberg-Osgoodformulation.

Compressiontestspecimen

Tensiontestspecimen


Task 2 – Aluminium Alloy analysis

• Extrudability;• Ductility;• Price;

• Yieldstress;• Ultimatestress• Yieldstrain;• Ultimatestrain;

• DeterminethebestsuitedalloytobeusedinBRD_ALproduction;

Maincriteriaforselectionofthealuminiumalloy

Parametersanalyses

Objective


Task 3 – Cross section analysis • Cyclictestsofextrudedprofilesfabricatedusing

thealuminiumalloydeterminedintheprevioustask;

• Extrudedprofileswillbesubjectedtouniaxialcyclicloadingwithcrescentamplitudeuntilfailure,followingtherecommendations:

– EN15129“Anti-seismicdevices”;

– ATC24“Guidelinesforthecyclicseismictestingofcomponentsofsteelstructures”;

– ECCSTGW1.31985“Recommendedtestingprocedureforassessingthebehaviour ofstructuralsteelelementsundercyclicloads


Task 3 – Cross section analysis Loadingtobeappliedtothecentreelementofthecross-sectionortothewholecross-section(tobeanalysed);

D

UniaxialcyclicprocedureusingUniversalmachineInstronatLERM(IST)

D

Fixedend

Extrudedprofile


Task 3 – Cross section analysis Objectives:

• Assessmentoftheinfluenceonhystereticbehaviourofkeyparameters:– Influenceofform;

– Influenceofgeometricrelationshipsbetween

dimensionsoftheelementsoftheextrudedprofile;

– Influenceofexistinggeometricimperfections(w0).

• Definitionofmostfavourablecrosssection

configuration;

• Definitionofrepresentativenumericmodelofthe

element,modellingtheisotropicandkinematic

hardeningphenomenaobservedduringthe

experimentaltests;

B

cb

t

Crosssectionexample


Task 4 – Global analysis - Experimental campaign to analyse the global hysteretic behaviour

Objectives:

• Analysisoftheeffectsofboundaryconditionsandglobalin-planeandout-of-planeimperfectionsonthehystereticbehaviouroftheassembly;

• Definitionofnumericmodelglobalsystemdulycalibratedfromexperimentalresults.

• Sameloadingprogrammehasintask3

RCReactionwall

mechanicalactuator

D

Steelprofile–Elasticzone

BRD_AL–Yieldzone Strong

floor


Task 5 – Case study - Development of numerical analyses of an existing pre-code pilotis building in Lisbon;

Objectives:

• Assessmentofdynamicbehaviouroftheexistingpre-codebuildingconsideringtheperformancerequirementsandcompliancecriteriaofENNP1998-1andEN1998-3;

• AssessmentofdynamicbehaviourofthecasestudybuildingwhenBRD_ALisusedhasstructuralretrofittingtechnique;

• NumericalanalysesonthecasestudybuildingwillperformedusingOpenSeesandBuilt-Xnumericalsoftwareusingthenumericalmodelofthenon-linearbehaviourofBRD_ALdulycalibratedduringtask4;


Chronogram and tasksTask 2017 2018 2019 2020 20211

2

3

4

5

6

start 1st year 2nd year 3rd year End

Task1– Stateoftheartreview,PhDcoursesofhostinstitution;Contactswithnationalandinternationalpartnersfor

thedevelopmentofBRD_AL;

Task2– Definitionofthealuminiumalloy.(Mechanicalcharacterizationofaluminiumalloys);

Task3–Crosssectionanalysis(CharacterizationofthehystereticbehaviouroftheBRD_AL);

Task4– GlobalAnalysis.(Characterizationofthehystereticoftheglobalsystem;

Task5– Casestudyanalysis;

Task6– Writingofthesis


ReferencesCalado,L.,Proença,J.M.andPavlovcic,L. Chapter3- Devices.[bookauth.]F.M.Mazzolani.EarthquakeProtectionofHistoricalBuildingsByReversibleMixedTechnologies– Volume2:SeismicProtectionofHistoricalBuildings:GuidetoMaterialandTechnologySelection.s.l. :Polimetrica– InternationalScientificPublisher,2012.Antonucci,R.,etal. Struttureprefabbricateconcontroventidissipativi:l'esempiodelnouvopolodidatticodellaFacoltàdiIngegnariadell'UniversitàPolitecnicadelleMarchediAncona.s.l. :UniversitàPolitecnicadelleMarche,Ancona[inItalian],2006.FedericoMazzolani,LuisCalado,Introductiontoreversiblemixedtechnologies,FP6PROHITECprojectAlmeida,A.B. Seismicretrofitofreinforcedconcretebuildingstructureswithbucklingrestrainedbraces.s.l. :ThesissubmittedinpartialfulfillmentoftheMScdegreeinCivilEngineering(Structures)inIST(SupervisorsProença,J.M.andGago,A.S.),2011.EN10002-1– “Tensiletesting-Part1:Methodoftestatambienttemperature;EN15129- “Anti-seismicdevices”;ATC24- “Guidelinesforthecyclicseismictestingofcomponentsofsteelstructures”;ECCSTGW1.31985- “Recommendedtestingprocedureforassessingthebehaviour ofstructuralsteelelementsundercyclicloads;FahnestockL.A.,SauceR.,RiclesJ.M.,Seismicresponseandperformanceofbuckling-restrainedbracedframes,JournalofStructuralEngineering,ASCE2007,Vol.133,pp.1195-1204;F.M.Mazzolani,A.Mandara,G.DiLauro,Plasticbucklingofaxiallyloadedaluminiumcylinders:anewdesignapproach,CMIS’04,FourthInternationalConferenceonCoupledInstabilitiesinMetalStructures,Rome,Italy,27-29September2004;G.DiMatteis,F.M.MazzolaniandS.Panico,PureAluminiumshearpanelsasdissipativedevicesinmomentresistingsteelframes,JournalofEarthquakeEngineeringandStructuralDynamics,2007,Vol.36,pp841-859.


ReferencesG.DiMatteis,G.Brando,F.M.Mazzolani,PureAluminium:Aninnovativematerialforstructuralapplications,JournalofConstructionandBuildingMaterials,2012,Vol.26,pp677-686.Chu-LinWang,TsutomiUsami,JyunkiFunayama,FumiakiImase,Low-cyclefatiguetestingofextrudedaluminiumalloybucklingrestrainedbraces,JournalofEngineeringStructures,2013,Vol.46,pp294-301.WorldAluminium- http://www.world-aluminium.org/publications/EuropeanAluminium- https://www.european-aluminium.eu


Thankyouforyourattention.

development of brd al prototyperbento/tmp/infrarisk-/summer... · 2018-07-18 · 0 7502 26405 39895...

Documents