=

NSSR=

SWrucWural Analysis of HisWorical ConsWrucWions – Jerzy Jasieńko (ed) © 2012 DPNH ProcławH PolandH ISSN 0860-2395H ISBN 978-83-7125-216-7

pbfpMfC BbeAsflro lc A obeABfifTATba Colpp sAriT Mouzakis ChKNI Adami ChK-bKOI harapitta iKPI sintzileou bK4 ABpToACT tithin=the=framework=of=kfhbo=project=EcmTJbksJOMMVJNFI=the=seismic=behaviour=of=subassemblies=before=and=after= interventions= is= investigatedK=tith= this=general=purposeI=a= series=of=biJaxial=shaking=table=tests=are=performed=on=a=subassembly=that=consists=of=a=cross=vault=resting=on=two=parallel=piersK=cor= the= execution= of= testsI= the= shaking= table= facility= of= ibbLkqrA= is= being= usedK= qhe= original=specimen=was=constructed=and=tested=previously=within=a=research=program=related=to=the=monument=of=hatholikon= of= aafni= jonastery= xNzK= After= the= completion= of= the= testing= campaign= of= the= asJbuiltJspecimenI= the= subassembly= is= strengthened= using= timber= struts= and= steel= ties= in= the= cross= vault= and=external =vertical =prestressing =in =the =piersI =as =well =as =grouting =of =masonryK =qhen =the =specimen =is =reJtested=and=the=behaviour=of=the=strengthened=specimen=is=compared=to=that=of=the=original=oneK=mrior=to=the= earthquake= tests= of= both= the= unJstrengthened= and= strengthened= subassemblyI= the= dynamic=properties= of= the= specimen= are= assessed= through= whiteJnoise= or= sweep= testsK= qhe=comparison= of= the=performance=of=the=subassembly=before=and=after=strengthening=highlights=the=positive=effect=Ein=terms=of=capacityI= observed= damages=and=relative=displacementsF= of= the=selected= intervention= techniques= to=the=seismic=behaviour=of=the=modelK= heywords: phaking table testsI Cross vaultI droutingI pteel elementsI Timber elements NK fNTolarCTflN =saults =are =quite =frequently =met =in =cultural =heritage =buildingsI =where =they =are =used =to =bridge =large =spansK=eoweverI=the=system=of=vaults=and=the=vertical=elements=supporting=them=is=rather=vulnerable=to=seismic=actionsK=ActuallyI= even=under= vertical= loads=aloneI= the=vaults= exert= horizontal= forces= to= their=supports=Ethe=horizontal=component=of=the=thrust=lineFK=qhusI=the=vertical=supporting=elementsI=namelyI=masonry=piers= or= wallsI= are=subjected=to=outJofJplane=bendingK=As= the=outJofJplane= flexural= stiffness=and=capacity= of= masonry=are= lowI= the=horizontal= component= of= the= thrust= line=may= lead= to=outwards=displacements=of= the=supports=of= the=vault=andI=henceI= to=damages= in=the=vault=andLor=damages=of= the=vertical= supporting= masonry= elementsK= qhe= situation= is= obviously= significantly= aggravated= when=seismic=actions=of=alternating=sign=occurK=qhe=behavior=of=vaulted=structures=is=investigated=by=means=of=testing=an=adequate=subassembly=on=the=earthquake= simulatorK= After= the= occurrence= of= severe= but= repairable= damagesI= the= subassembly= is=repaired= and= strengthened= using= techniques= aiming=at= EaF= grouting= of= all= cracks= in= the= vault= and= the=archesI=EbF=strengthening=of=masonry=through=groutingI=EcF=enhancement=of=the=capacity=of=piers=to=outJofJplane= bending= through= external= vertical= prestressing= and= EdF= alleviation= of= the= effects= of= the=horizontal=component=of=the=thrust=lineI=through=the=arrangement=of=timber=struts=and=steel=ties=at=the=

================================================N Assistant=mrofessorI=kational=qechnical=rniversity=of=AthensI=pchool=of=Civil=bngineeringI=iaboratory=

of=barthquake=bngineeringI=harrismo]centralKntuaKgr=O arK=Civil=bngineerI=kational=qechnical=rniversity=of=AthensI=pchool=of=Civil=bngineeringI=iaboratory=

of=oeinforced=ConcreteI=adamis]centralKntuaKgr=P arK=Civil=bngineerI=kational=qechnical=rniversity=of=AthensI=pchool=of=Civil=bngineeringI=iaboratory=

of=barthquake=bngineeringI=klucia]centralKntuaKgr=4 mrofessorI=kational=qechnical=rniversity=of=AthensI=pchool=of=Civil=bngineeringI=iaboratory=of=oeinforced=

ConcreteI=elvintz]centralKntuaKgr=

=

NSSS=

base=of=the=archesK=fn=what=followsI=the=experimental=program=is=presented=and=the=main=test=results=are=discussed=and=commented=uponK=====OK abpCofmTflN lc pmbCfMbN =qhe=original=subassembly=xNz=consists=of=a= cross=vault= that= rests=on=two=parallel=piersI=made=of= threeJleaf=stone=masonryK=qhe=specimen=was=constructed=according=to=the=typology=and=the=properties=of=the=original=materials=of=the=masonry=of=aafni=jonasteryK=aue=to=the=limitations=of=the=shaking=simulator=E4KMM=×=4KMM=platformFI=the=model=was=built=in=reduced=scale=of=OWP=EcigK=NFK===

= aF= bF==

================ = cF= dF=

cigK N=aF=qhe=cross=vaultX=bFI=cF=Arches=during=constructionX=dF=bxperimental=setJup=of=the=original=subassembly=on=the=shaking=simulator=

=qhe=dimensions=of=the=specimen=in=plan=are=OKTMR=×=OKSM=mOK=qhe=piers=are=OKSM=m=highI=whereas=the=total=height=of=model=is=approxK=equal=to=OKUR=mK=qhe=piers=are=MK4R=m=thickK=qhe=two=exterior=leaves=of=piers= of= the= model= are=of= unequal= thickness= ENVO= mm= and=NPR= mmFK= joreoverI= the= external= leaf= is=made=of=bigger=stones= than=the=internal=oneI=whereas=solid=bricks=are=arranged=along=both=horizontal=and=vertical= joints= in= the=external=masonry= leafK=qhe=thickness=of=stones= in=both= leaves=was=varyingI=both=inJlength=and=inJheight=of=wallsK=qhusI=the=thickness=of=the=intermediate=filling=material=Emade=of=small= stones= and= mortarF= is= also= varying= both= horizontally= and= vertically= Eaverage= thickness= Z=NOP=mmFK=Concerning=the=materials=used=for=the=construction=of=the=piersI=a=travertine=having=similar=properties= to= those= of= the= inJsitu= main= type= of= stones= was= usedK= Based= on= the= type= of= mortar=encountered= on= the= monumentI= a= limeJpozzolan=mortar= with= a= mixed=aggregate= matrix= composed= of=siliceous=river=sand=and=limestone=gravels=was=designedK=qhe=inner=part=of=the=piers=was=a=mix=of=small=stones=and=mortarK=aetailed=data=related=to=the=properties=of=the=piers=of=the=subassembly=can=be=found=in=xOzK=qhe=cross=vault= was=made=of=solid=bricksI= similar= to=those=of=the=original=structureK=qhe=cross=vault=was=constructed=with=solid=bricksK=qhe=specimen=was=constructed=on=a=steel=base=EcigK=NdFK=As= mentioned= aboveI= before= reJtesting= the= model= within= kfhbo= projectI= several= repair= and=strengthening=techniques=were=applied=on=the=specimenI=namelyW===

aF= drouting= of= diagonal= cracks= occurred= in= the= piersK= cor= this= purposeI= a= natural= hydraulic= lime=based=grout=developed=using=pCB=material=was=applied=xPzK=

bF= oepair=of=the=arch=and=the=vault=Eby=means=of=groutingFK=

=

NSST=

cF= pince= cross= vaults= are= very= vulnerable= when= the= piers= are= subjected= to= outJofJplane= actionsI=horizontal=timber=elements=EstrutsF=and=steel=elements=EtiesF=were=positioned=in=order=to=improve=the=connection=between=vault=and=piers=EcigK=OFK==

dF= cinallyI= the=piers= were=strengthened= for=outJofJplane= bendingI= using=prestressed=Ccom= platesK=qhe=plates=used=EpfhAJCarboaur=SO4F=were=placed=vertically=on=both=faces=of=the=piers=EcigK=PFK=A= total= of= NMM= kk= prestress= force= was= applied= in= each= of= the= four= piersI= corresponding= to=a=compressive=stress=equal=to=MKOM=jmaK=

==

=

cigK O mositioning=of=timber=and=steel=elements=at=the=base=of=the=arch=of=the=vault==

=

cigK P deneral=view=of=the=repairedLstrengthened=specimen=on=the=shaking=simulator=

=PK TbpT pbT-rm =qhe=experimental=setup=is=shown=in=cigure=PK=qhe=specimen=was=securely=fastened=on=the=shaking=table=through=the=rigid=steel=baseK=qhe=instrumentation=used=in=the=shaking=table=experiments=was=designed=so=as=to=measure=the=accelerations=along=u=and=v=directions=at=the=top=of=the=specimenI=the=acceleration=and= the=absolute= displacement= at= the= top= and= base= of= piers= along=u= and= v= directions= EcigK= 4FK= qhe=acceleration= and= the= displacement= of= the= shaking= taking= table= were= also= recorded= during= each= testK=AdditionallyI=strain=gauges=were=used=to=measure=the=strain=of=the=prestressed=Ccom=platesK=

=

NSSU=

===========

aNT=EuF

aN4

aNP

aNO

aNN

aNM

aV

aT

aU

AOu

Z

u

D4X

A8X/A9Y

Z

S4 (interior leaf)S1 (extrerior leaf)

S3 (interior leaf)S2 (extrerior leaf)

D2YA13Y

D5Y

A4X/A5Y

D1X

A10X/A11Y

D3YA12Y

=========================================aF==============================================================================bF=

cigK 4 jeasurement=points=of=acceleration=and=displacement=for=the=aF=asJbuilt=and=bF=strengthened=specimen=

=4K fNmrT MlTflN ANa TbpTfNd molTlCli

=4KNK Base motion qests= were= performed= using= the= signals= recorded= at= Calitri= during= the= OP= kovember= NVUM= frpinia=earthquake=Ejs=Z=SKVFK=qhe=basic=features=of=recorded=accelerations=are=the=long=duration=Eof=the=order=of= VM=secF= and= the= sequence= of= two= main= shocks= of= similar= peak= accelerationK= cor= the= execution= of=testsI= the=reference=base=input=consists=of=the=first=section=of=the=long=inputI=of=about=4M=sec=durationK=qhese=shorter=excitations=have=frequency=content=similar=to=that=of=long=excitationsK=Both=bJt=and=kJp=components=were=applied=in=the=horizontal=u=and=v=direction=respectivelyK=qhe=time=histories=of= the=base=accelerations=are=shown=in=cigure=RI=while=the=corresponding=response=spectra= for=RB=damping=are=depicted=in=cigure=SK==

=

0 R 10 1R 20Time (sec)

-2.00

-1.00

0.00

1.00

2.00

Base

Acc

eler

atio

nX

(m/s

2 )

==0 R 10 1R 20

Time (sec)

-2.00

-1.00

0.00

1.00

2.00

Base

Acc

eler

atio

nY

(m/s

2 )

=aF bF=

cigK R frpinia=earthquakeW=Base=acceleration=time=histories=along=aF=u=direction=and=bF=v=direction=

=

0 1 2 3Time (sec)

0.00

2.00

4.00

6.00

oes

pons

eA

ccel

erat

ion

X(m

/s2 )

===0 1 2 3

Time (sec)

0.00

2.00

4.00

6.00

oes

pons

eA

ccel

erat

ion

Y(m

/s2 )

=aF bF=

cigK S frpinia=earthquakeW=Base=acceleration=time=histories=along=aF=u=direction=and=bF=v=direction==

4KOK Testing procedure qhe=test=procedure=consisted= in=a=series= of= seismic= tests=on= the=strengthened=subassemblyI=using=the=shaking= table= of= iaboratory= of= barthquake= bngineering= at= kqrAK= cor= the= sake= of= comparisonI= the=experimental= campain= carried=out=by= xNz= on= the=unstrengthened= specimen= was= also= followed= for= the=strengthened=oneK=qables=N=and=O=show=the=test=protocol=for=the=two=conditionsI=namelyI=before=EBpF=

=

NSSV=

and=after= strengthening=EApFK= ft= is= noted=thatI= in=both=casesI= the=model=was= subjected=to=subsequent=increased=scaled=motions=up=to=appearance=of=significant=damageK=

=Table N=rnstrengthened=specimenW=mrotocol=of=tests=

=

koK=of=test= bxcitation= airection=of=excitation=

Amplification=of=original=record==

EBF=NBp= thiteJnoise= v= –=OBp= thiteJnoise= u= –=PBp= thiteJnoise= w= –=4Bp= frpinia=earthquake= u= PM=RBp= frpinia=earthquake= u= RM=SBp= frpinia=earthquake= u= TR=TBp= frpinia=earthquake= u= NMM=UBp= frpinia=earthquake= u= NOR=VBp= frpinia=earthquake= u= NRM=NMBp= frpinia=earthquake= u= NTR=NNBp= frpinia=earthquake= u= OMM=NOBp= frpinia=earthquake= u= ORM=NPBp= frpinia=earthquake= u= PMM=N4Bp= frpinia=earthquake= u= PRM=NRBp= frpinia=earthquake= u= 4MM=NSBp= frpinia=earthquake= u= 4RM=NTBp= frpinia=earthquake= u= RMM=NUBp= frpinia=earthquake= uJv= RM=NVBp= frpinia=earthqauke= uJv= NMM=OMBp= frpinia=earthqauke= uJv= NRM=

Concerning= the=unstrengthened=specimenI= the= subassembly=was= tested=under= earthquake=excitationsI=first=in=the=longitudinal=direction=EuF=and=then=in=both=longitudinal=EuF=and=transversal=EvF=directionsK=mrior= to=earthquake=testsI= the=dynamic=properties=of= the=specimen=were=assessed=through=whiteJnoise=testsK=qhe=experimental=campaign=is=shown=in=qable=NK=fn=detailI=the=original=specimen=was=subjected=to= several= excitations= in= u= direction= with= the= base= acceleration= increased= gradually= up= to= RMMB= of=original= recordK= auring=qest= NMBpI= where= the=base= acceleration= along=u= direction= was= amplified= to=NTRB= of= original= recordsI= cracks= appearedK= fn= subsequent= tests= along= u= directionI= the= specimen=suffered= increasing= level= of= damage=as= the= excitations= became= more=severeK= qhenI= three=biaxial= tests=were=executed=with=the=base=acceleration=increased=stepwise=up=to=NRMB=of=original=recordsK=

Table O=ptrengthened=specimenW=mrotocol=of=tests=

=

koK=of=test= bxcitation= airection=of=excitation=

Amplification=of=original=record==

EBF=NAp= pineJsweep= u= –=OAp= pineJsweep= v= –=

Application=of=vertical=load=of=the=postJtensioned=system=PAp= pineJsweep= u= –=4Ap= pineJsweep= v= –=RAp= frpinia=earthquake= v= RM=SAp= frpinia=earthquake= u= NMM=TAp= frpinia=earthquake= u= NRM=UAp= frpinia=earthquake= u= OMM=VAp= frpinia=earthquake= u= ORM=NMAp= frpinia=earthquake= u= PMM=NNAp= frpinia=earthquake= u= PRM=NOAp= frpinia=earthquake= u= 4MM=NPAp= frpinia=earthquake= u= 4RM=N4Ap= pineJsweep= u= –=NRAp= pineJsweep= v= –=

=

NSTM=

fn=the=case=of=the=strengthened=specimen=Efor=details=see=qabK=OFI=the=base=accelerations=were=amplified=to=various=values=of=pgaI=up=to=4RMB=of=the=original=recordK=fn=other=wordsI=the=strengthened=specimen=withstood= three= times= higher= seismic= input= than= the= unstrengthened= specimen= EqabK=NFI= in= terms= of=maximum=accelerationK==fn=order=to=identify=the=dynamic=characteristics=of=the=modelI=sine=logarithmic=sweep= tests= were= also= executedK= ft= is= noted= that= sweep= tests= performed= both= prior= and= after= the=application= of= the= postJtensioning= systemI= separately= along= each= one= of= the= horizontal= u= and= v=directionK=joreover=and=in=order=to=determine=the=change=in=the=dynamic=properties=of=the=specimen=after=the=damageI=this=procedure=was=repeated=after=the=completion=of=shaking=table=testsK==RK TbpT obpriTp

=RKNK lbserved damages Both=before=and=after=the=application=of=the=repairLstrengthening=techniquesI=the=specimen=was=visually=examined=and=the=observed=cracks=were=plotted=after=each=excitationK==

=RKNKNK rnstrengthened ppecimen auring=qest=OMBp=ENRMB=of=frpinia=earthquakeFI=the=specimen=suffered=several=damages=as=shown=in=cigure =TK =fn =detailI =due =to =outJof =plane =bending =the =cross =vault =was =detached =from=the =piersI =cracks =were=formed=at=the=arches=Eat=the=brickLmortar=interfaceFI=whereas=horizontal=cracks=were=formed=at=the=piers= Eat=both=sides= of= the=masonryFK= curthermoreI= a= permanent= deformation=Eequal= to=NR=mmF=of= the=specimen=along=its=vertical=axis=was=recordedK===RKNK2K ptrengthened ppecimen qhe=damages=observed= in=the=strengthened=specimen=at=the=end=of=biaxial=tests=were=similar=to=those=presented=by=the=asJbuilt=specimenK=lf=courseI=in=the=case=of=the=strengthened=specimenI=the=damages=occured= at= higher= values= of= the= base= accelrationK= fn= detailI= during= qest= VApI= in= which= the= base= ==

====== == aF== bF==

===== == cF== dF=

cigK T rnstrengthned=specimenK=lbserved=damages=at=aF=the=piersI=bF=the=arches=and=cF=and=dF=at=the=vault==

acceleration=was=scaled=up=to=ORMB=of=the=original=recordsI=cracks=were=formed=at=the=south=arch=Eat=the=brickLmortar=interfaceF=of=the=strengthened=specimenK=auring=the=same=testI=cracks=started=forming=also=at=the=cross=vaultK=qhese=cracks=appeared=at=the=region=of=connection=between==the=vault=and=the=

=

NSTN=

piers =Ebetween =the =two =prestressed =Ccom=platesFK =fn =subsequent =testsI =the =cracks =became =larger =and =they=propagated=towards= the=archI=as=well=as= the=top=of= the=vaultK=AdditionallyI=damages=occurred=in=both=archesK=qhe=crack=pattern=at=the=end=of=the=testing=procedure=is=presented=in=cigure=UK=ft=has=to=be=mentioned= thatI= no= damages= were= visible= at= the= piersK= eoweverI= after= the= completion= of= the=experimental=campain=and=the=removal=of=the=prestressing=systemI=the=appearance=of=horizontal=cracks=at=the=base=of=the=piers=was=evident=as= in=case=of=the=unstrengthened=specimenX=they=were=of=smaller=opening=thoughK=

=

= ==

= aF= bF==

= ==

= cF= =dF==

cigK U ptrengthened=specimenK=Cracks=at=the=end=of=qestingW=aF=crossJvault=EintradosFX=bF=crossJvault=EextradosFX=cFW=north=archX=dFW=south=arch=

=RKOK aynamic characteristics of specimens fn =qable =PI =the =frequencies =and =their =damping =are =presented =for =whiteJnoise =tests =along =u =and =v =directions= for= the= unstrenthened= specimenK= qhe= frequencies= were= calculated= using= the= transfer=functions=of=recorded=response=acceleration=and=input=base=accelerationK=qhe=damping=was=calculated=from=the=transfer=function=plots=by=applying=the=halfJpower=bandwidth=method=xPzK==cor =the=strengthened=specimenI =sine=logarithmic=sweep=tests =were=performed=at =several =stages=of =the=experimental=campainI=separately=along=the=u=and=v=directionK=qhe=frequency=range=was=between=NKM=ez=and=PO=ez=at=a=rate=of=one=octave=per=minute=with=an=amplitude=of=MK4M=mLsecO=EMKM4=gFK=fn=qable=4I=the= natural= frequencies= and= the= damping= ratios= are= given= at= the= several= stages= of= the= experimental=procedure=for=the=strengthened=specimenK==

=Table P=rnstrengthened=specimenW=aynamic=characteristics=

=

qest=koK= airection= crequency=EezF=

aamping=ratio=EBF=

NBp= u= NOKPM= NKMM=

OBp= v= RKVS= OKMM=

=

NSTO=

Table 4=ptrengthened=specimenW=aynamic=characteristics==

qest=koK==

airection= crequency=EezF=

aamping=ratio=EBF=

NAp= u= NMKSU= PK4T=

OAp= v= PKRO= 4KST=

Application=of=vertical=load=of=the=postJtensioned=system=

PAp= u= NPKNR= PK4R=

4Ap= v= 4KVU= 4KUM=

N4Ap= u= NOKPU= PK4U=

NRAp= v= PKTU= SKVS=

=fn=both=the=asJbuilt=and=the=strengthened=specimenI=there=is=a=significant=difference=in=frequency=along=the=two=main=directionsK=qhe= low=stiffness=of= the=subassembly=along=the=v=axis= is= evidenced=by= the=lower=frequency=values=as=compared=to=those=measured=along=the=u=axis=Esee=qabK=P=and=qabK=4K=ln=the=other=handI= the=grouting= = together=with=the= =horizontal=elements=Esteel= ties=and=wooden=strutsF= led=to=a =signficant = =increase =of =the =value =of =the =damping =ratio =Efrom =approxK =N =and =OB =at =the =u =and =v =direction =to =P =and =4BI =respectivelyFI =as =well =as =to =a =decrease =of =the =frequencyI =as =the =subassembly =became= stifferKqhe= subsequent= application= of= the= external= vertical= prestressing= has= led= to= further=increase =of =the = =frequency =of =the =specimen =in =both =directions =Eu =and =vFI =whereas = =the =value =of =the =damping=ratio=remained=practically=the=sameK=After= the=completion=of= the=tests= Eqest=NPApW=4RMB=of= frpinia= earthquakeI= tabK=OFI=a=decrease= in=the=frequency=of =the=specimen=mainly=in=v=direction=was=measured=Esee=qests =4Ap=and= =NRApI=qabK =4FI =due=to=the=damage=that=had=occurred=at=the=arches=and=the=vaultK=ln=the=contraryI=the=dampingI=mainly=in=v=directionI=was=increasedK==RKPK oelative displacement and acceleration at the top fn=qable=RI=the=relativeI=to=the=baseI=displacements=at=top=of=piers=are=given=together=with=the=absolute=recorded=peak=values=of=accelerations=for= the=unstrengthened=specimen=Eqests=NVBpW=NMMB=of=frpinia=earthquake=and=OMBpW=NRMB=of=frpinia=earthquakeFK=fn=qable=SI=the=corresponding=values=are=given=for=the=strengthened=specimen=Eqest=SApW=NMMB=of=frpinia=earthquakeI=TApW=NRMB=of=frpinia=earthquake=and=NPApW=4RMB=of= frpinia=earthquakeFK=Τhe=comparison=of= the=results=presented=in=qables=R=and=S=shows=that=for=the=same=seismic=input=ENMMB=or=NRMB=of=frpinia=earthquakeF=the=relative=displacements=in =the =vJdirection =are =more =or =less =equal =for =the =two =conditions =of =the =specimen =Ebefore =and =after =interventionsFK= qhis= proves= that= the= interventions= led= to= reJinstatement= of= the= overall= stiffness= of= the=subassembly=in=its=weak=directionK=qhe=same=holds=true=for=the=accelerations=measured=at=the=top=of=the=piers=before=and=after=strengtheningK===ln=the=other=handI=the=strengthening=of=the=subassembly=has=proven=to=be=efficientI=as=the=strengthened=specimen= EaF= was= able= to= withstand= significantly= higher= seismic= input= E4RMB= versus= NRMB= of= the=frpinia=earthquakeF=and=EbF=it=withstood=significantly=larger=deformations=along=both=u=and=v=axes=Esee=qable=SFK= ft= is= important= to=note= that= the=damages= that= occurred= to= the=strengthened=subassembly=are=similar= in= morphologyI= as= well= as= in= intensity= with= those= observed= on= the= asJbuilt= subassemblyI=although=the=specimen=at=its=strengthened=state=was=subjected=to=a=significant=number=of=tests=at=higher=seismic=input=valuesK========

Table R=rnstrengthened=specimenW=qop=acceleration=and=relative=displacement==

koK=of=test= Acceleration=EmLsecOF=

oelative=aisplacement=

EmmF=

AOu= ARv= oaOMv=

NVBp=ENMMB=of=frpinia=earthquakeF= NKST= OKU4= 4KPN=

OMBp=ENRMB=of=frpinia=earthquakeF= OKPS= RKNN= NNK4O=

=

NSTP=

Table S=ptrengthened=specimenW=qop=acceleration=and=relative=displacement==

koK=of=test= Acceleration=EmLsecOF=

oelative=aisplacement=

EmmF=

ANMu= ANPv= oaOv=

SAp=ENMMB=of=frpinia=earthquakeF= NKVT= PKPT= RK4S=

TAp=ENRMB=of=frpinia=earthquakeF= PKMP= 4KUR= VKNT=

NPAp=E4RMB=of=frpinia=earthquakeF= NMKPT= VKSP= 4MKRT=

====SK ClNCirpflNp =ln=the=basis=of=the=experimental=results=presented=in=this=paperI=the=following=conclusions=can=be=drawnW=

NK qhe=vulnerability=of=vaulted=structures=perpendicularly=to=the=supporting=masonry=elements=was=evident= both= before= and= after= strengthening= of= the= subassembly= Edamages= concentrated= in= the=vaultI=in=the=archesI=as=well=as=at=the=top=and=the=bottom=of=the=piers=due=to=out=of=plane=bendingFK=

OK qhe=selected=intervention=techniques=were=successfulI=as=they=have=led=to=a=significant=increase=of=the=maximum=base=acceleration=the=subassembly=could=withstandI=as=well=as= to= the=deformation=capacity=of=the=specimen=along=both=its=main=axesK=

PK ft= should= also= be= mentioned= that= the= intervention= techniques= applied= to= the= subassembly= are=acceptable=for=historic=structuresK=ActuallyI=EaF=the=use=of=timber=andLor=steel=struts=and=ties=is=quite=common= in= historic= structuresI= even= at= the= time= of= their= constructionI= EbF= the= external= vertical=prestressing=constitutes=a=NMMB=reversible=techniqueI=whereas=EcF=grouting=is=of=general=acceptanceI=although=it=is=clearly=a=non=reversible=techniqueK=cinallyI=

4K ft= is= considered= that= the= scheme= of= interventions= is= acceptableI= as= it= improves= the= seismic=behaviour= of= the= subassembly= without= altering= the= original= function= of= the= bearing= systemK=ActuallyI= the= damages= observed= in= the= strengthened= model= are= similar= to= those= of= the=unstrengthened=specimenI=whereas=the=dynamic=characteristics=of=the=subassembly=at=both=states=Ebefore=and=after=interventionF=are=similar=for=similar=seismic=inputsK==

AChNltibadbMbNTp =qhis= research=was=carried=out=within=the=cmT=funded=buropean=mrogramme=kfhbo=Emroject=Contract=koK=O44NOPFI=httpWLLwwwKnikerKeuLK=qhanks=are=due=to=pfhA=ebiiAp=fndustrial=C=Commercial=pKAK=and=ptresseead=Ad=for=the=design=and=the=application=of=the=external=vertical=prestressing=systemK== obcbobNCbp xNz Carydis=mKI=jouzakis=eKI=harapitta=iK=EOMMTF=fnvestigation=of=mechanical=behaviour=of=byzantine=

type= masonry= with= or= without= mosaic= and= evaluation= of= different= interventions= techniquesW=Application=to=the=hatholikon=of=aafni=jonasteryK=Technical oeport ibbLkTrA Ein=dreekFK

xOz sintzileou= bKI= jiltiadouJcezans= AKI= srouva= AKI= Anagnostopoulou= pK= EOMMSF= jechanical=properties=of=threeJleaf=stone=masonryK=fnW mroceedings of the fnternational Conference ptructural Analysis of eistorical Constructions pAeCMSI kew=aelhiI=fndiaK=

xPz Badogiannis= bKI= halagri= AKI= fpsilanti= bKI= aedeloudis= CKI= sintzileou= bK= EOMNOF= jix= design= and=performance=evaluation= of= grouts= with= superfine=natural=pozzolanI= submitted= fn mroceedings of the fnternational Conference ptructural Analysis of eistorical Constructions pAeC 2MN2I=troclawI=molandK

x4z Clough=oKtK=menzien=gKI=ENVTRF=aynamic=of=ptructuresI=edK=jcdraw=eillI=kew=vorkK=