=

NUTP=

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

SEISMIC ASSESSMENT OF MUiTIJiEAF MASONRY STRENGTHEN WITH INgECTIONS OR TRANSVERSAi TIES Alberto jauroNI dianmarco ae celiceO ABSTRACT =oecent=earthèuakes=highlighted=the=vulnerability=çf=multiJleaf=wallsI=which=tend=tç=fail=çutJçfJplane=by=disaggregatiçn=çf=the=external=leavesK=qherefçreI=strengthening=technièues=are=çften=necessaryI=in=çrder=tç=imprçve=the=transversal=bçnd=between=the= leavesI= ensuring=a= mçnçlithic=behaviçur=çf= the=wallK= fn=the=present=paper=a=mçdelling=strategy=is=presented=which=makes=it=pçssible=tç=evaluate=the=respçnse=çf=rubbleJstçne=masçnry=walls= in=presence= çf= different= strengthening= interventiçnsI= including= inàectiçns=çf=mçrtar=and=insertiçns=çf=tie=bars=thrçughçut=the=thickness=çf=the=wallK=qhe=apprçach=is=based=çn=the=distinct= element= methçdI= where= the= stçnewçrk= is= regarded= as= an= assembly= çf= rigid= blçcks= and= the=mçrtar =àçints =are =simply =regarded =as =nçn =linear =interfaces =with =cçhesiçn =and =frictiçnK =Aiming =at =reprçducing= the= shape= and= pçsitiçn= çf= the= stçnes= within= the= wallI= particular= care= is= taken= in= the=definitiçn=çf= the=meshI=which= is=generated=frçm=the=survey=çf=existing=masçnry=sectiçnsK=qhe=mçdel=prçves=able=tç =capture=the=essential =feature=çf =the=behaviçur =çf =ancient =masçnryI =which=relies =çn=the=mçrphçlçgy=çf= the=wall=rather= than= çn=the=mechanical=prçperties= çf= the=cçmpçnentsK=qwç=bçundary=cçnditiçns=are=then=investigatedI=iKeK=cantilever=wall=and=wall=cçnstrained=at=the=tçp=by=means=çf=a=ring=beamK=qhe=respçnse=çf=the=stçnewçrk=is= finally=evaluated=by=means=çf=static=pushJçver=analysesK=qhe=results=highlight=the=effects=and=efficacy=çf=the=strengthening=technièues=çn=the=failure=mechanism=and=çn=the=çutJçfJplane=capacity=çf=multiJleaf=masçnry=wallsK==heywordsW jasonryI ptrengthening techniquesI fnjectionsI qie barsI aistinct blement jethod NK INTRODUCTION =aamages=surveyed=after= the=earthèuake=çf=i’Aèuila=in=OMMV=cçnfirm=that=perimeter=walls=are=amçng=the= mçst= vulnerable= elements= çf= histçrical= cçnstructiçnsK= fndeedI= when= multiJleaf= masçnry= is=encçunteredI=these=walls=are=prçne=tç=detach=frçm=the=rest=çf=the=structure=and=tç=fail=çutJçfJplane=by=disaggregating=intç=different=partsK=qhis=cçllapse=mechanism=may=invçlve=cçmpletely=the=wall=çr=çnly=its=external=partI=cigK=NaJNbI==and=is=mçstly=due=tç=the=absence=çf=transversal=bçnd=between=the=leaves=çf=the=wallI=which=is=related=tç=the=manufacturing=prçcess=rather=than=çn=the=mechanical=prçperties=çf=the=cçnstituentsI= iKeK=mçrtar=and= stçnesK= AnywayI= different= factçrs= may= additiçnally=affects= masçnry=disaggregatiçn=increasing= the=cçmplexity=çf= the=prçblemK=cçr= instanceI= the=experience=gained=during=the= past= seismic= events= highlights= hçw= the= presence= çf= cçncrete= ring= beamsI= which= were= widely=adçpted= in=the=past= fçr= retrçfitting=masçnry=cçnstructiçnsI= may=trigger=and=amplify=disaggregatiçn=çf=the=stçnewçrkI=cigK=NbJNcK=As=a=matter=çf=factI=the=efficiency=çf=the=latter=interventiçn=is=the=çbàect=çf=a=lçng=çnJgçing=debate=within=the=technical=cçmmunityI=accçrding=tç=which=the=presence=çf=cçncrete=beams=is=thçught=either=tç=strengthen=the=cçnstructiçnI=by=prçviding=a=bçx=behaviçurI=çr=tç=weaken=the=wallI=by=increasing=leaf=disaggregatiçnK===

===================================================N=mhaI=aeptK=çf=ptructuresI=rniversity=oçma=qreI=sia=`çrradç=pegre=SI=MMN4S=oçmeI=ftalyI=maurça]unirçmaPKit=O=mrçfessçrI=aeptK=çf=ptructuresI=rniversity=oçma=qreI=sia=`çrradç=pegre=SI=MMN4S=oçmeI=ftalyI=

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FigK N `çllapse=çf=multiJleaf=masçnriesW=aF=partial=separatiçn=çf=the=external=leaf;=bF=cçmplete=disaggregatiçn=çf=the=stçnewçrk;=cJdF=failures=prçbably=related=tç=the=presence=çf=cçncrete=ring=beams=

=ft=is=wçrth=pçinting=çut=that=if=transversal=bçnd=is=prçvided=by=an=accurate=pçsitiçning=çf=header=stçnes=which=span=the=whçle=thickness=çf=the=wallI=as=suggested=by=açnghi=in=NVPR=xNzI=the=latter=may=exhibit=a=nearly=mçnçlithic=behaviçurK=qhe=recent=earthèuake=çf=i’Aèuila=clearly=çutline=hçw=multiJleaf=walls=suppçsedly= made= with= similar= cçmpçnents= may=act= differently= depending= çn= masçnry= mçrphçlçgyK=AccçrdinglyI= a= realistic= predictiçn= çf= the= failure= mechanisms= which= the= wall= may= develçp= prçves=crucial=bçth= fçr=perfçrming=a= reliable=vulnerability= assessment= and= fçr= designing=the=mçst= effective=strengthening= technièuesK= qhis= issue= received= increasing=attentiçn=and=recently=has=been= included= in=the=ftalian=natiçnal=standard=xOzI=accçrding=tç=which=the=effect=çf=masçnry=mçrphçlçgy=shçuld=be=taken=intç=accçunt=by=designers=when=perfçrming=vulnerability=analyses=çf=existing=cçnstructiçnsK=jçreçverI=in=case=disaggregatiçn=intç=different=leaves=is=likely=tç=çccurI=prçper=measures=shçuld=be=taken=in=çrder=tç=imprçve=the=transversal=bçnd=and=tç=ensure=a=mçnçlithic=behaviçur=çf=the=wallK=keverthelessI=there=is=a=lack=çf=indicatiçns=and=numerical=tççls=suitable=either=fçr=analysing=the=mechanical=behaviçur=çf=multiJleaf=walls=çutJçfJplane=lçaded=çr=fçr=evaluating=the=effectiveness=çf=the=strengthening=technièues=cçmmçnly=adçpted= çn=this= type=çf=masçnryK= As=a= matter= çf=factI= the=effects=çf= masçnry=mçrphçlçgy=and= çf= retrçfitting= interventiçns= çn= the= behaviçur= çf= stçne= masçnry= walls= have= been= çnly= partially=investigated= by= the= technical= cçmmunityK= jçst= çf= the= cçntributiçns= presented= in= the= literature= are=devçted=tç=study=the=behaviçur=çf=masçnry=walls=shçwing=a=mçnçlithic=behaviçur=either=by=means=çf=experimentatiçn=xPI=4z=çr=by=means=çf=numerical=simulatiçns=xRzK=lne=çf=the=piçneer=wçrks=analyzing=the= influence= çf= masçnry= mçrphçlçgy= is= frçm= diuffrè= xSzI= whç= investigated= the=behaviçur= çf= walls=made= with= wellJshaped= stçne= masçnry= Elpus quadratumFK= peveral= cçntributiçns= have= been= then=

=

NUTR=

devçted= tç= analysing= the= mechanical= behaviçur= çf= rubble= masçnry= with= bçth= numerical= and=experimental=analyses=and=with=a=view=tç=strengthening=technièuesI=xTJNNzK=qhere=are=still=few=wçrks=available= in= the= literatureI= which= investigate= the= behaviçur= çf= rubble= masçnry= walls= under= seismic=actiçnsK=fn xNOz=shake=table=tests=çn=OLP=scale=masçnry=buildings=reinfçrced=with=different=retrçfitting=interventiçns= were= cçnductedK= jçre= recentlyI= an= experimental= campaign= was= carried= çut= by= the=rniversity=çf=maduaI=cçnsisting=çf=a=set=çf=shake=table= tests=aiming=at= investigating=the=efficiency=çf=strengthening=technièues=çn=the=behaviçur=çf=multiJleaf=masçnry=panels=excited=çutJçfJplane=xNPzK=qhe=preset=wçrk= intends= tç=give=a=cçntributiçn=in=the=same=directiçn=by=means=çf=numerical=analyses=perfçrmed=adçpting=the=distinct= element=methçdK= fn=the=first=part= the=apprçach=çriginally=prçpçsed=in=xN4z= fçr= the= analysis= çf= multiJleaf= masçnry= walls= is= extended= in= çrder= tç= include= the= mçdelling= çf=cçncrete=ring=beams=and=çf=twç=strengthening=interventiçnsI=namely=inàectiçns=çf=mçrtar=and=insertiçns=çf=transversal=tie=barsK=qhe=case=çf=a=stçne=masçnry=wallI=which=belçngs=tç=the=set=çf=specimens=tested=in=xNPzI= is=analyzedK=qhe=mesh=is=autçmatically=generated=frçm=the=phçtçgraphic=surveys=çf= the=wall=and=reprçduces=the=actual=pçsitiçn=çf=the=stçnes=within=the=sectiçn=çf=the=panelK=fn= the= secçnd=part= the= results=çf= static=pushçver= analyses=are=presented=which= have=been=cçnducted=cçnsidering=either=the=panel=simply=resting=çn=the=base=çr=the=panel=cçnstrained=at=the=tçpK=cinallyI=the=çutJçfJplane=capacity=çf=the=wallI= evaluated=accçunting=fçr= masçnry=mçrphçlçgyI= fçr= the=presence=çf=ring=beams=and=retrçfitting=technièuesI=is=cçmpared=against=the=respçnse=çf=mçnçlithic=wallsK=qhe=aim=is= tç=preliminarily= investigate=the=efficiency=çf= the=interventiçns= in=prçviding=transversal=bçnd=tç=the=stçnewçrk=and=tç=what=extent=the=presence=çf=cçncrete=ring=beams=may=affect=leaf=disaggregatiçnK=

=OK DISTINCT EiEMENT MODEiiING =fn=the=fçllçwingI= the=case=çf=a= threeJleaf=wall= made=çf= stçne=masçnry= is=analyzedI=cigK=OaK=qhe=wallI=which=has=size=MKR=×=OKT=×=NKP=mPI=has=been=tested=during=the=experimental=campaign=cçnducted=by=the=rniversity= çf= madçva= within= the= ambit= çf= the= oeluis= prçàect= xNPzK= qhe= external= leaves= cçnsist= çf=limestçne=masçnry=while=the=inner=cçre=is=made=çf=incçherent=fragments=çf=the=same=type=çf=stçneK=fn= çrder= tç= investigate= the= mechanical= behaviçr= çf= the= wall= tçwards= çutJçfJplane= çverturning=mechanismsI=a=plane=mçdel=based=çn=the=distinct=element=methçd=has=been=adçptedK=qhe=pçsitiçning=çf=the=stçnes=alçng=the=transversal=sectiçn=çf=the=panel=has=been=reprçduced=in=a=`Aa=fçrmat=çn=the=basis= çf= the=wall=phçtçgraphic=surveys;=a= distinct= element= mesh= has= been= then=generated= in=which=the=stçne=blçcks=are=represented=as=pçlygçnal=elements=and=the=àçints=are=reduced=tç=zerçJthickness=interfacesI=cigK=ObJOcK=ptçne=elements=are=mçdeled=as=rigid=blçcks=having=density=çf=NU=hkLmPK=qhe=interfaces=shçw=an=elastçJfragile=behaviçr=when=subàected=tç=tractiçnI=and=an=elastçJplastic=behaviçr=when=subàected=tç=shear=and=cçmpressiçnI=cigK=OfK=fn= the=elastic=rangeI=the=respçnse=çf=the=àçints= is=cçntrçlled= by= stiffnesses= in= nçrmal= and= tangential= directiçnsI= dençted= as= hn= and =htI= respectivelyK=qhese=stifnesses=are=thçught=tç=have=marginal=effects= in=the=analysesI=unless= they=result=excessively=lçw= tç= induce= exceeding= levels= çf= blçcks= interpenetratiçnsI= which= wçuld= result= in= an= unrealistic=behaviçr=çf=the=wallK=ln=the=çther=handI=excessively=high=values=risk=tç=remarkably=increase=the=time=fçr= the= analysisI= xNRzK= cçr= these= reasçnsI= the= whçle= set= çf= àçints= has= been= assigned= axial= and=tangential=stifnesses=hn===R=·=NMV==kLm=and=ht===OKN=·=NMV=kLmI=respectivelyK=`çncerning=the=parameters=which=cçntrçl=the=nçnJlinear=behaviçr=çf=the=interfacesI=a=jçhrJ`çulçmb=failure=criteriçn=has=been=adçptedK=ft=is=cçnvenient=tç=distinguish=twç=sets=çf=àçints=within=the=wallW=the=àçints=belçnging=tç=the=external=leaves=çf=the=wall=have=been=assigned=a=tensile=strength=ftIe===MKN=jma;=the=àçints=belçnging=tç=the=inner=cçre=and=thçse=dividing=the=cçre=frçm=the=external=leaves=çf=the=wall=have= been= assigned= a= null= tensile= strength= ftIi == MKM= jmaK Bçth= types= çf= àçints= have= been= assigned=a=frictiçn=angle φ===PM°K=qhe=mçdeling=strategy=thus=develçped= is= thçught= tç=reprçduce=the=essential=features= çf= histçrical= masçnry= behaviçrI= which= is= mainly= cçntrçlled= by= the= pçsitiçning= çf= the= stçne=elements= intç= the= wall=rather= than=by=the=mechanical=prçperties= çf= the=cçmpçnentsK= bventuallyI= twç=bçundary=cçnditiçns=have=been= examinedW= in= the= first= çne=the=wall= is= simply=resting=çn= the=grçundI=cigK=ObI=while=in=the=secçnd=çneI=the=wall=is=cçnstrained=at=the=tçp=by=means=çf=a=cçncrete=ring=beam=which=prevents=lateral=displacementsI=cigK=OcK=qhe=analyses=have=been=carried=çut=with=reference=tç=twç=strengthening=systemsW=inàectiçns=çf=mçrtar=and= insertiçn= çf= tie= bars= thrçughçut= the= thickness= çf= the= wallI= cigK= OdJOeK= qhe= fçrmers= have= been=mçdeled=by=saturating=the=gaps=between=the=stçnes=with=new=fictitiçus=elements=and=by=assigning=the=àçints= çf= the= inner= cçre= a= finite= tensile= strength= ftIiK= qhis= strategy= is= based= çn= the= assumptiçn= that=masçnry=is=sufficiently=permeable=enabling=the=mçrtar=tç=reach=the=inner=cçre=çf=the=wallK=qwç=values=

=

NUTS=

fçr=ftIi have=been=cçnsideredI=namely=MKMO=jma=and=MKM4=jmaK= ft= is=wçrth=nçting=that=these=values=are=cçnveniently= lçwer= cçmpared= tç= the= actual= mechanical= prçperties= çf= cçmmçn= mixturesK= qhis=assumptiçn=aims=at=accçunting=fçr=the=incçmplete=penetratiçn=çf=mçrtar=within=the=àçints=and=reèuires=future= experimental= validatiçnK= qie= bars= have= been= mçdeled= as= mçnçJdimensiçnal= elements= that=prçvide= a= null= reactiçn= under= cçmpressiçn= and= exhibit= an= elastçJplastic= behaviçr= under= tractiçnI=cigK=OfK=Bearing=in=mind=the=methçdçlçgy=adçpted=fçr=perfçrming=this=strengthening=interventiçnI=the=tangential= actiçn= exercised= by= the= wall= çn= the= lateral= surface= çf= the= bar= has= been= neglectedK=AccçrdinglyI= tie= bars= reactiçns= have= been= accçunted= fçr= çnly= as= cçuple= çf= fçrces= lçcated= çn= the=external=leaves=çf=the=panelK=ln=the=whçleI=three= levels=çf=bars=have=been=cçnsidered=which=have=an=area=eèual=tç=P=Ø=S=each=and=are=inserted=with=a=cçnstant=spacing=çf=MKT=m=starting=frçm=NLP=çf=the=wall=heightI=cigK=OeK==

=FigK O =deneratiçn=çf=the=distinct=element=mçdelW=aF=phçtçgraphic=survey;=bF=mesh=çf=the=wall=simply=resting=çn=the=base;=cF=mesh=çf=tçpJcçnstrained=wall;=dF=mçdelling=çf=mçrtar= inàectiçns;=eF=mçdelling=çf=tie=bars= inserted=trhçugçut=the=thickness=çf=the=wall;=fF=cçnstitutive=relatiçns=adçpted=fçr=the=behaviçur=çf=mçrtar=àçints=and=tie=bars=

=PK PUSHOVER ANAiYSES =qhe=seismic=capacity=çf=the=wall=under=cçnsideratiçn=has=been=assessed=by=perfçrming=static=pushçver=tests=using=the=cçmmercial=sçftware=rab`I=xNRzK=qhe=tests=have=been=carried=çut=applying=gravity=and=then=an=increasing=hçrizçntal=acceleratiçn=in=successive=steps;=fçr=each=step=the=analysis=is=perfçrmed=until= an= eèuilibrium= cçnfiguratiçn= is= attainedK= içad= steps= are= prçgressively= decreased= when=apprçaching=the=cçllapse=hçrizçntal=lçadI=which=is=defined=as=the=first=value=çf=acceleratiçn=fçr=which=the= respçnse= divergesK= qhe= previçus= given= acceleratiçn= whereby= the= wall= can= reach= an= eèuilibrium=cçnfiguratiçn=is=cçnsidered=as=the=çut=çf=plane=capacity=λ=EgFK=auring=the=analyses=the=displacement=d=çf=a=cçntrçl=pçint=is=recçrdedK=qhis=pçint=is=lçcated=at=the=tçp=çf=the=cantilever=wall=and=at=midJheight=çf= tçpJcçnstrained=wallK=qhe=results=çbtained=are=repçrted= in=cigK=PaJPb= in=terms=çf=pushçver=curves=where=the=applied=hçrizçntal=acceleratiçn=λ and=the=displacement=d==are=repçrted=as=relative=values=çf=the= cçllapse= acceleratiçn=λmon= and=ultimate= displacement= dmon= which= have= been= evaluated= in= case= çf=walls= having= the= same= dimensiçns= çf= the= çne= here= analyzed= and= exhibiting= a= perfect= mçnçlithic=behaviçrK=qhe=peculiarity=çf=the=aistinct=blement=jethçd=cçnsists=in=fçllçwing=the=mçtiçn=çf=the=wall=under= hçrizçntal= actiçn= in= finite= kinematics= and= in= cçnsideringI= during= the= analysisI= the= lçss= çr=fçrmatiçn=çf=new=cçntacts=between=adàacent=stçnesK=qhese=prçperties=make=the=prçpçsed=methçdçlçgy=particularly=suitable=tç=the=purpçse=çf=the=present=wçrkI=since=it=allçws=us=tç=reprçduce=the=prçgressive=cçllapse= çf= the= wallI= frçm= the= beginning= çf= separatiçn= intç= different= leaves= up= tç= the= cçmplete=disaggregatiçn=çf=the=wall=bçndK=cçr= instanceI=cigsK=4JR=shçw=the=cçllapse=mechanism=deriving=frçm=the=simulatiçns=perfçrmedK=fn=case=çf=walls=simply=resting=çn=the=base=and=in=absence=çf=strengtheningI=cigK=4I=the=cçllapse=çccurs=by=disàunctiçn=çf=the=external=leaveI=which=causes=a=reductiçn=çf=the=POB=in=terms= çf= cçllapse= acceleratiçn= and= çf= RUB= in= terms= çf= ultimate= displacement= when= cçmpared= with=mçnçlithic=wallsK=

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NUTT=

Adçpting=mçrtar=inàectiçns=able=tç=prçvide=tç=the=àçints=a=MKMO=jma=tensile=strengthI=a=O4B=and=RUB=increase= is= encçuntered= fçr= the= capacity= çf= the= wall= in= terms= çf= acceleratiçn= and= displacementI=respectivelyK= eçweverI= this= interventiçn= is= nçt= able= tç= prevent= the= disaggregatiçn= çf= the= stçnewçrk=during=the=pçstJpeak=phase=while=the=use=çf=strçnger=mçrtarI=having=tensile=strength=eèual=tç=MKM4=jmaI=makes=it=pçssible=tç=çbtain=a=nearly=mçnçlithic=behaviçrI=cigK=PaK=then=tie=bars=are=inserted=within=the=wallI=the=displacement=capacity=is=fully=recçvered=while=the=mechanism=is=activated=fçr=a=slightly=lçwer=acceleratiçn=with=respect=tç=the=mçnçlithic=wall=and=is=characterized=by=the=develçpment=çf=a= rçcking=hinge=lçcated=sçme=cçurses=abçve=the=base=çf=the=panelI=cigK=4dK==

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=bF=FigK P=mushçver= curves=expressed= in= terms=çf=hçrizçntal=acceleratiçn= λ=and=displacement=d=çf=the=cçntrçl=pçint=nçrmalized=with=respect= tç=the=cçllapse=acceleratiçn= λmon= and=the=ultimate=displacement=dmon çf=the=mçnçlithic==================================================wallW=aF=cantilever=wall; bF==tçp=–=cçnstrained=wall==talls=cçnstrained=at=the=tçp=exhibit=higher=çutJçfJplane=capacityI=cigK=SW=in=absence=çf=strengtheningI=the=cçllapse=çccurs=by=separatiçn=çf=the=external=leave=whichI=under=increasing=hçrizçntal=acceleratiçnI=develçps= three= hinges= lçcated= at= the= tçpI= at= the= base= and= at= apprçximately= OLP= çf= the= wall= heightI=respectivelyK=lnce=the=maximum=acceleratiçn=is= attainedI= the=capacity=çf= walls= rapidly=decreases= tç=zerçK= qhe= case=under= cçnsideratiçn=shçws= a= 4UB= and= VMB= reductiçns= in= terms= çf= acceleratiçn= and=ultimate=displacementI=cçmpared=tç=the=theçretical=mçdel=cçnsisting=in=a=system=çf=mçnçlithic=blçcksI=cigK=PbK=fn=presence=çf=a=ring=beam=lçcated=çn=the=tçpI=the=effect=çf=inàectiçns=seems=nçt=sufficient=tç=prevent= the= disaggregatiçn= çf= the= wall= intç= different= leavesW= it= çnly= entails= a= mçdest= increase= in=cçllapse=acceleratiçn=EHN4BI=HO4BF=while=the=displacement=capacity=remains=substantially=unchangedK=ln=the=cçntraryI=transversal=tying=prevents= the=separatiçn=çf=the=wall=bçnd=andI=therefçreI=permits=tç=çbtain=bçth=an= increase= in= terms=çf=peak=acceleratiçn= EH4OBF= and=a= remarkably= increase= in= terms= çf=displacement=capacity=EH=PRMBFI=cigK=PbK=

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=4K CONCiUSIONS =qhe= present= wçrk= represents= a= first= attempt= tç= adeèuately= mçdel= the= effectiveness= çf= strengthening=technièues= fçr= increasing= the= seismic= capacity= çf= multiJleaf= stçne= masçnry= wallsK= qhe= assessment=methçdçlçgy=prçpçsed=prçves= able=tç= estimate=the= reductiçn= çf= the=seismic=capacity= çf= this= type=çf=walls=cçmpared=tç=the=widely=adçpted=mçdel=çf=mçnçlithic=blçcks=and=the=influences=çf=strengthening=interventiçns= such=as= inàectiçns= and= tie=barsK= qhe=preliminary= results= here=presented= çutline= tç= what=extent= the= effect= çf= these= interventiçns= depends= çn= the= bçundary= cçnditiçns= çf= the= wallW= in= case= çf=cantilever=walls=bçth=mçrtar=inàectiçns=and=transversal=tie=bars=may=prçvide=a=mçnçlithic=behaviçr=tç=the= wall;= çn= the= çther= handI= in= case= çf= walls= cçnstrained= at= the= tçp= by= means= çf= a= ring= beamI= the=cçncentratiçn= çf= stresses= çn= the= external= leaves= facilitates= the= prçcess= çf= wall= disaggregatiçn= even=when=cçhesiçn=is=prçvided=within=the=stçnewçrk=by=means=çf=inàectiçnsK=eçweverI=this=finding=needs=tç= be= validated= by= a= wider= recçrd= çf= cases= and= tç= be= cçnfirmed= by= experimental= evidencesK= qhe=analyses=cçnducted=sç=far=reveals=the=feasibility=çf=the=prçpçsed=apprçach=fçr=assessing=the=respçnse=çf=stçne=walls=by=duly=accçunting=fçr=wall=texture=and=fçr=the=presence=çf=strengthening=systemsK=fn=çrder=tç= enrich= the=preliminary= results= here= çbtainedI= further= numerical= simulatiçns= are=scheduled=fçr= the=future=in=which=the=behaviçr=çf=panels=having=different=masçnry=mçrphçlçgies=will=be=investigated=by=perfçrming=time=histçry=analyses=under=bçth=acceleratiçn=pulse=and=natural=accelerçgramsK=

=ACKNOWiEDGEMENTS =qhe= financial= suppçrt= prçvided= by= the= research= prçgramsW= “aipartimentç= di= mrçteziçne= `ivile= –=`çnsçrziç= obirfpI= qhematic= Area= NI= oesearch=iine=NI= qask=N= signed= çn=OMMVJMVJO4”=and=“mofk=OMMV=mrçàectW=jetçdçlçgie=di=Analisi=e=jçdellaziçne=di=jurature=jultistratç=per=la=`çnservaziçne=del=`çstruitç=ptçricç”=is=gratefully=acknçwledgedK====REFERENCES xNz açnghiI=aKI=NVPRK=januale dell’architettoI=qçrinçI=ftalyW=rniçne=qipçgracç–bditrice=qçrineseK=xOz `çnsigliç=puperiçre=dei=iavçri=mubbliciI=OMMVK=`ircçlare=MO=febbraiç=OMMV=nK=SNT=fstruziçni=per=

l’applicaziçne=delle=“kuçve=nçrme=tecniche=per= le=cçstruziçni”=di= cui= al=aj=N4=gennaiç=OMMUK=dazzetta rfficiale della oepubblica ftaliana nK 4TI pupplemento lrdinario nK OTI=oçmaK==

xPz ABhI= NVUNK= jethodology for mitigation of seismic hazards in existing unreinforced masonry buildingsW wall testingI out of planeK=qçpical=oepçrt=M4K=Agbabian=AssçciatesI=bl=pegundçK=

x4z Al =phawa =lKI =de =celiceI =dKI =jaurçI =AKI =pçrrentinçI =iKI =OMNOK =lut =çf =plane =seismic =behaviçur =çf=rçcking=masçnry=wallsK=barthquake bngineering and ptructural aynamicsI=4NERFW=V4VJVSUK=

xRz driffithI= jK`KI= iamI= kKqKhKI= tilsçnI= gKiKI= açhertyI= hKI= OMM4K= bxperimental= investigatiçn= çf=roj=walls=in=flexureI=ApCbW gournal of ptructural bngineeringI=NPMEPFW=4OPJ4POK=

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xSz diuffrèI=AKI=NVVSK=A=mechanical=mçdel=fçr=statics=and=dynamics=çf=histçrical=masçnry=buildingsK=fn mrotection of the Architectural eeritage Against barthquakesI Cfpj Courses and iectures noK PR9I=edited=by=sK=metrini=and=jK=paveK=rdineI=fqI=ppringerJserlagI=TNJNROK=

xTz BindaI=iKI=minaJeenrièuesI=gKI=AnzaniI=AKI=cçntanaI=AKI=içurencçI=mKBKI=OMMSK=A=cçntributiçn=fçr=the= understanding= çf= lçadJtransfer= mechanisms= in= multiJleaf= masçnry= wallsW= qesting= and=mçdelingI=bngineering ptructuresI=OUEUFW=NNPOJNN4UK=

xUz `çrradiI= jKI= qedeschiI= `KI= BindaI= iKI= BçrriI= AKI= OMMUK= bxperimental= evaluatiçn= çf= shear= and=cçmpressiçn= strength= çf= masçnry= wall= befçre= and= after= reinfçrcementW= deep= repçintingI=Construction and Building jaterialsI=OOE4FW=4SPJ4TOK=

xVz lliveiraI= aKsKI= içurenççI= mKBKI= darbinI= bKI= salluzziI= jKoKI= jçdenaI= `KI= OMMSK= bxperimental=investigatiçn=çn=the=structural=behaviçur=and=strengthening=çf= threeJleaf=stçne=masçnry=wallsI= fn=mroceedings of the pAeC’MSI Rth fnternational Conference on ptructural Analysis of eistorical ConstructionI=kew=aelhiI=fndiaI=UNTJUOSK=

xNMz salluzziI=jKoKI=aa=mçrtçI=cKI=jçdenaI=`KI=OMM4K=Behaviçr=and=mçdeling=çf=strengthened=threeJleaf=stçne=masçnry=wallsI=jaterials and ptructuresI=PTEPFW=NU4JNVOK=

xNNz BçrriI=AKI=`çrradiI=jKI=pperanziI=bKI=diannantçniI=AKI=OMNMK=oeinfçrcement=çf=histçric=masçnry=with=high=strength=steel=cçrdsI=jasonry fnternationalI=OPEPFW=TVJUTK=

xNOz açlceI=jKI=mçnzçI=cK`KI=dçrettiI=AKI=jçrçniI=`KI=diçrdançI=cKI=ae=`aniçI=dKI=jarnettçI=oKI=OMMUK=Pa= aynamic= tests= çn= OLP= scale= masçnry= buildings= retrçfitted= with= different= systemsI= in=mroceedings of the N4th torld Conference on barthquake bngineeringI=BeiàingI=`hinaK=

xNPz salluzziI= jKoKI= jazzçnI= kKI= OMNMK= Comportamento ainamico di mannelli in juratura jultistrato in mietraW mrove pperimentali cuori dal miano svolte presso il CK oK bkbA “la Casaccia”I=repçrt=internçI=rniversità=degli=studi=di=madçvaK=

xN4z de= celice= dKI= OMNNK= lutJçfJplane= seismic= capacity= çf= masçnry= depending= çn= wall= sectiçn=mçrphçlçgyI=fnternational gournal of Architectural eeritageI=RE4FW=4SSJ4UOK=

xNRz ftasca=cçnsulting=grçup=fncKI=NVVSK=rabCJrniversal distinct element codeI version PKM – rser’s manualI=jinneapçlisI=jinnesçtaK=