Transcript
Page 1: bkbodvmmolefkkivpfplcplkov lirkplkcfkbatfedcombpelkaba ... · NUSU= M 2 4 S 8 NM N N M R NM NR M R PM PR M frequenxez inertanxEcm/s^Fkz Z pmq p_Z pPM pmp == MMMMM MMMM MMMM MMMMS

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

bkbodv AmmolACe fk AkAivpfp lc MAplkov ClirMkp Clkcfkba tfTe dcom Mbpe Blkaba lk pTfcc Aka cibufBib Aaebpfsbp Arkadiusz hwiecieńNI Bogusław wającO ABpToACT =Application=of=com=confinement= sóstem=improves= strength=of= the=masonró=column=but=also=changes=their=dónamic=responseK=joreoverI= stiff= Emineral=and=epoxóF=adhesivesI=used= in=the=strengthening=of=masonró=columnsI=do=not=protect=enough=strengthening=fibres=against=the=damage=caused=bó=pressure=of= sharp= fragments= of= masonró= columnsI= especialló= during= structural= degradation= under= static= and=dónamic= actionK= qhis= stress= concentration= effect= can= be= reduced= bó= the= use= of= polómer= flexible=adhesivesK==qhe= paper= presents= results= of= static= and= dónamic= testing= of= five= masonró= columnsW= one= of= them=unconfined=and=four=of=them=strengthenedI=using=confinement=made=of=dcom=meshK=Confinement=was=bonded=to=the=masonró=columns=on=mineralI= epoxó=and=two=kinds=of=polómer=adhesivesK=ppecimens=were=tested=first=dónamicalló=to=find=influence=of=various=tópes=of=confinement=on=differences=in=their=dónamic=responseK=kextI= all=the=specimens=were=investigated=during=a=compression=test=up= to=failure=using=a=universal=machineK=Analóses=of=the=static=and=dónamic=tests=of=the=specimens=were=carried=out=using=energó=approachK=Comparison=of=obtained=results=allowed=presenting=dónamic=effectiveness=of=various= tópes= of= adhesives= in= the= case= of= confining= application= in= earthquake= protectionI= and= also=allowed= calculating= damage= energó= ratio= of= tested= solutionsK= cinallóI= all= specimens= were= tested=staticalló=up= to= failure=with= observation= of= damage= energóK= lbtained=postJcritical= damage= energó= of=specimens=Eimportant=for=safetó=of=structureF=was=comparedK==heywords: jasonry columnsI dcom confinementI aynamic testingI ptiff and flexible adhesives NK fkTolarCTflk

NKNK sulnerability of masonry columns jasonró= columns= are= structural= elements= that= are= vulnerable= to= dónamic= forces= and= usualló= do= not=have=enough=postJcritical=damage=energóI=because=of=their=brittlenessK= ft=is=visible=especialló= in=cases=of=earthquakesI=where=horizontal=and=vertical=dónamic=loads=excide=strength=of=masonró=columns=and=collapse= mechanism= is= rapidK= lverload= of= this= kind= of= structural= elements= has= often= catastrophic=consequences= thus= methods= of= columns=capacitó= improvement=are=wantedK= crom=the=safetó=point=of=viewI= not= onló= strength= is= taken= into= consideration= in= case= of= earthquake= but= also= ductilitó=EdeformabilitóF= and= damping= properties= are= importantK= _rittle= failure= of= masonró= columns= is= the=problem=that=should=be=eliminated=in=seismic=areasK==

NKOK Confining of masonry columns Confinement=sóstem=of=masonró=column=using=com=composites=is=one=of=the=most=effective=innovative=techniques= of= repair= and= protectionK= qhis= strengthening= method= is= based= on= various= kinds= of= com=composites=made=of=carbonI=glassI=aramide=or=basalt=fibersI=produced=in=form=of=meshI=barsI=laminates=or= matsK= janó= tests= were= performed= bó= scientists= to= find= the= most= effective= combination= of=strengthening=sóstem=consisting=of=com=composites= and=various= kinds= of= adhesives= xNJPzK=qhe=most=popular=are=mineral=and=epoxó=adhesives=but=these=materials=are=of=brittle=behaviorK=ptiff=EmineralF=and=================================================N=mhKaKI=Cracow=rniversitó=of=qechnologóI=akwiecie]pkKeduKpl=O=mhKaKI=Cracow=rniversitó=of=qechnologóI=boguslawUzajac]gmailKcom=

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veró= stiff= EepoxóF= adhesivesI= using= in= strengthening= of= masonró= columnsI= do= not= protect= enough=of=strengthening=fibers=against= the=damage=caused=bó=pressure=of=sharp=fragments= of=masonró=columns=x4JRz=during=structural=degradationK=qhis=is=the=reason=of=low=efficiencó=in=taking=advantage=of=fibers=capacitóI= because= of= stress= concentration= appearanceK= qhe= other= aspect= of= confining= is= the= dónamic=behavior= of= strengthened= columnsK= Confinement= sóstems= change= dónamic= properties= of= existing=columns=which=influence=their=dónamic=responseK=

NKPK fnfluence of stiff and flexible adhesives fixing com composites ptrengthening= of= existing= brittle= masonró= columns= at= earthquake= areas= is= tópical= protection= against=dónamic= forcesK= rsing= of= brittle= adhesives= does= not= protect= the= com= against= sharp= fragments= of=masonró=x4z=and=causes=stiffening=of=columnsI= increasing=resonance=frequencó=of=themK=As=a=solution=to=this=problem=the=use=of=polómer=flexible=adhesives=is=proposed=which=allow=reducing=peak=stresses=xSz= and= do= not= change= significantló= dónamic= properties= of= strengthened= masonró= columns= xTzK=qópicallóI=strengthening=confinement=sóstems=are=tested=in=static=investigations=and=dónamic=tests=are=carried= out= sporadicallóK= qhe= research= presented= in= this= paper= show= how= innovative= technologó= of=confiningI= based= on= flexible= polómer= adhesives= modifies= dónamic= properties= in= comparison= to=traditional=stiff=onesKI=dcom=meshes=are=veró=popular=from=the=economic=point=of=viewI=thus=this=kind=of=fibers=was=applied=in=tested=specimensI=presented=in=this=paperK===OK Clkcfkfkd lc MAplkov ClirMkp tfTe dcom Mbpe OKNK aescription of tested columns cive=specimens=were=tested=dónamicalló=and=next=staticalló=up= to=failureI=which=were=constructed= in=form=of=masonró= columns= of= dimension=ORM=×= ORM=×=RMM=mmK=qheó= consisted= of= T=brick= laóers= of=thickness= SR= mm= made= of= the=molish= _onarka= brickI= joined= with= cement= mortar= laóers= of= thickness= =TKR= mm= made= of= fzolbetK= lne= column= was= tested= without= strengthening= and= four= of= them= were=strengthened=using=confinement= made=of= dcom= meshI= bonded= to=masonró= specimens= with=stiff= and=flexible=adhesivesK=ptiff=adhesives=were=made=of=stiff=mineral=cement=mortar=fzolbet=and=of=stiff=epoxó=resin=pikadur=PMK=clexible=adhesives=were=made=of=hard=flexible=polómer=mq=and=of=middle=flexible=polómer=mpK=qhe=view=of=one=of=the=columns=and=of=the=applied=dcom=mesh=was=presented=in=cigK=NK= OKOK Materials properties A= pullJoff= test= using= cólinder= of= diameter= RM= mm= was= used= to= obtain= tensile= strength= of= bricks= =Ethe=average=value=from=S=specimens=was=OKMS=jma=with=the=coefficient=of=variation=Cos=of=NTKRBF=and=mortar=Ethe=average=value=from=S=specimens=was=NKOP=jma=with=the=Cos=of=TKPBFK=AdditionallóI==

u=

v=

======

5 mm

Y

X

=

cigK N=jasonró=columns=confined=with=dcom=mesh=EleftF=and=the=zoom=of=the=dcom=mesh=ErightF= threeJpoint=bending=tests=were=also=doneK=_rick=specimens=EOM=unitsF=of=dimension=ORM=×=NOM=×=SR=mm=were=bending=at= the=support=distance=of=OM=cmI=resulting=in=the=average=value=of=OKMV=jma=with=the=

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Cos=of=NVKNBK=qhe=same=test=Eaccording=to=bk=VVUJO=xUzF=was=carried=out=for=the=mortar=specimens=of=dimension=4M=×=4M=×=NSM=mmI=bó=bending=them=at=the=support=distance=of=NM=cmK=qhe=obtained=average=value=of=tensile=strength=for=S=units=was=PKNS=jma=with=the=Cos=of=NMK4BK=qhe=average=compression=strength=of=bricks=E4=specimensF=of=dimension=ORM=×=NOM=×=SR=mm=was=OPKP=jma=with=the=Cos=of=NSKT=B=and=of=mortar=ENO=specimensF=of=dimension=4M=×=4M=×=4M=mm=was=NRKV=jma=with=the=Cos=of=TKPBK=qhe=economó=and=popular=dcom=mesh=EN4T=gLmOFI=used=in=civil=engineering=for=warming=of=masonró=buildingsI=was=appliedK=qhis=kind=of=dcom=meshes=is=constructed=of=glass=fibers=of=tópe=b=of=following=parametersW r=Z=OR=kkLmPI=tensile=strength=of=N=TMM=jmaI=voung=modulus=of=TO=MMM=jma=and=ultimate=strain= of= MKNMBK= CrossJsection= of= fiber= weaves= in= the= u= direction= was= NRU·NMJS= mOLm=and= in= the= v=direction=is=NUT·NMJS=mOLmK=bach=of=the=four=tested=specimens=were=confined=with=4=laóers=of=the=dcom=meshI=bonded=using=various=kinds=of=adhesives=EcigK=NFK= OKPK mroperties of stiff and flexible adhesives qhe=stiff=mineral=adhesive=Ecement=mortar=fzolbetF=properties=were=characterized=aboveK=qhe=stiff=epoxó=adhesive=Epikadur=PMF=had=the=following=propertiesW=the=voung=modulus=of=NO=UMM=jmaI=tensile=strength=of=OU=jmaI=shear=strength=of=NU=jmaI=adhesion=[=4=jma=and=ultimate=strain=of=MKOOBK=qhe=hard=flexible=adhesive=Epolómer=mqF=had=the=following=propertiesW=the=voung=modulus=of=SMM=jmaI=tensile=strength=of=NU=jmaI=shear=strength=of=NU=jmaI=adhesion=[=R=jma=and=ultimate=strain=of=NMBK=qhe=middle=flexible=adhesive=Epolómer= mpF=had=the=following=propertiesW= the=voung=modulus=of=U=jmaI= tensile=strength=of=OKO=jmaI=shear=strength=of=MKU=jmaI=adhesion=of=OKR=jma=and=ultimate=strain=of=4RBK==PK MAplkov ClirMkp TbpTba avkAMfCAiiv

PKNK Test description cive=masonró=specimens=fixed=elasticalló=at=the=bottom=were=excited=using=of=a=modal=hammerK=At=the=top= of= columnsI= an= additional= mass= of= PR= kg= was= joinedI= to= increase= a= dónamic= response= of= the=masonró=specimenK=fmpulse=excitations=were=generated=at=the=top=of=the=tested=columns=in=a=horizontal==

=====

corc

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z

qime xsz

EaF

qime xsz

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atio

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lera

tion

xcm

/s2 z

=

EcF

=

cigK O=jasonró=column=fixed=elasticalló=to=the=bottom=and=excited=at=the=top=of=specimen=using=a=modal=hammer=EleftF=and=signals=recorded=in=timeJdomainW=EaF=dónamic=force=–=modal=hammerI=EbF=acceleration=–=top=of=columnI=

EcF=acceleration=–=bottom=of=column=ErightF==

direction=and=dónamic= responses= of= specimens=were=measured=using= two=accelerometers= Eone=at= the=top=and=one=at=the=bottom=of=each=columnF=–=cigK=OK=qhere=were=used=the=accelerometers=PRS_NU=mC_I=

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the= modal= hammer= mC_= MUSaRM= and= the= recording= sóstem=ijp= pCAaAp= jl_fibI= collecting= in=time=domain=data=of=excitation=impulse=forces=and=acceleration=responses=at=the=top=and=at=the=bottom=of=columns=EcigK=OFK=qhe=sampling=frequencó=was=OM4U=samplesLsecondK=bach=specimen=was=excited=bó=the=modal=hammer=NM= times=and=the=most= representative=signal=had=been=chosen=for=analósisK=qo=avoid= influence=of= bottom=vibration=on= the=rest= of= the= tested=columnI= the=specimen’s= responses= were=corrected=in=frequencó=domain=according=to=equation=ENFK==

==

crequency xezz

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zz

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=

=

crequency xezz

ccq

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zz

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=

cigK P=crequencó=characteristics=EccqF=presented=for=the=exemplaró=unconfined=masonró=column=–=specimen=EwFW=EaF= FEwc =J=force=of=modal=hammer=impulseI=EbF= FEwu&& =–=real=acceleration=Eaccording=to=equation=ENFF=at=the=top=

of=specimen====

bottomtopuuu FEFEFE w-w=w &&&&&& = ENF=

=whereW= FEwu&& = Z==real=acceleration=frequencó=characteristic=EccqF=at=the=column=topI===

topu FEw&& = Z==measured=acceleration=frequencó=characteristic=EccqF=at=the=column=topI=

=bottom

u FEw&& =Z==measured=acceleration=frequencó=characteristic=EccqF=at=the=column=bottomK=

= w= Z==natural=angular=frequencó=in=xradLsz=

PKOK Measurement data analysis qested=specimens=are=shortló=named=in=bracketsW=masonró=column=without=confinement= EwFI= confined=column= with= polómer= mq= adhesive= Ew|p|mqFI= confined= column= with= mortar= adhesive= Ew|p|wFI=confined= column= with= epoxó= adhesive= Ew|p|PMF= and= confined= column= with= polómer= mp= adhesive=Ew|p|mpFK=pignals=without=noise=Emodified=according=to=equation=ENFF=of=each=specimen=were=selected=for= analósisK=qhe=force=and=acceleration=signals= in=timeJdomain=were=analózed=using=the=cast=courier=qransform=EccqFK=qhe=frequencó=characteristics=EccqF=for=the=exemplaró=unconfined=masonró=column=–= specimen= EwF= are= presented= in= cigK= PK= lne= of= them= is= the= force= characteristic= of= modal= hammer=impulse= FEwc =and=the=second=one=is=real=acceleration=characteristic=Eaccording=to=equation=ENFF=at=the=top= of= specimen= FEwu&& K =pimilar =pairs =of =the =frequencó =characteristics =EccqF =were =obtained =also =for =confined=masonró=columnsK=qhe=obtained=in=frequencó=domain=characteristics=of=the=impact=force=and=of=the=horizontal=acceleration=allowed=determining=xTI=Vz=the=modulus=of=the= inertance=function=fEwFI=given= bó= equation= EOF= and= the= modulus= of= the= compliance= EreceptanceF= function= AEwF= according= to=equation =EPFK =qhese =dónamic =characteristics =are =presented =in =cigK =4 =for =each =tested =specimenI =to =compare= them= each= otherK= qhe= diagrams= allowed= finding= dominant= response= frequencies= of= each=specimen= Ew= –= N4= ezI= w|p|mq= –= N4= ezI= w|p|w= –= OT= ezI= w|p|PM= –= OO= ezI= w|p|mp= –= NV= ezFI=indicating=their=stiffness=increase=after=confining=Eresonant=frequencó=increaseFK==

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zZZ_p_mqZ_p_ZZ_p_PMZ_p_mp

==M,MMMM

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M R NM NR 2M 2R PM PR 4Mfrequency xezz

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xcm

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ZZ_p_mqZ_p_ZZ_p_PMZ_p_mp

=

cigK 4=qhe=frequencó=characteristic=obtained=for=tested=masonró=columns=of=the=inertance=function=fEwF=–=left==and=of=the=compliance=function=AEwF=–=right=

PKPK motential energy of tested specimens qhe=dónamic=excitation=EseismicF=energó=is=transmitted=to=the=structure=and=it=is=balanced=bó=capacitó=of=the=structure=to=absorb=this=energóK=ft=is=possible=to=determine=the=input=energó=in=the=moment=when=the= velocitó= of= structure= is= equal= zeroK= fn= this= caseI= the= input= energó= bi= equals =the =sum =of =xTzW =the =kinetic= energó= Ebk= Z=MFI =the =potential =energó =bp= Ereaching= the= maximum=and= representing= reversible=elastic= deformationFI= damping= energó= bd= Ewhich= is= dissipated= through= the= mechanism= of= viscous=dampingF=and=irreversible=hósteretic=energó=bh=Eabsorbed=bó=the=structure=through=controlled=nonlinear=deformationsFK= Assuming= that= onló= vibrations= in= the= elastic= range= of= columns= are= taken= into=considerationI= the= equation= of= energó= balance= can=be= written= in= form=E4FK= qhusI= the= input= energó=bi=acting=for= tested=columns= Efor= real= structure=at= low=level=of= dónamic=excitationF= is=balanced=onló=bó=maximum=potential=energó=bp=and=damping=energó=bdK== === dphki bbbbub ++=+=== max}M{}M{FME & = E4F==

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Z Z_p_mq Z_p_Z Z_p_PM Z_p_mp

bp normalized x-z

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1,00

0,68

0,21

0,38 0,35

M,M

M,2

M,4

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M,8

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Z Z_p_mq Z_p_Z Z_p_PM Z_p_mp

aamping coefficient x-z

=

cigK R=Comparison=of=normalized=potential=energó=|bpEwF|normalized=EleftF=and=of=normalized=damping=coefficients=xnormalizedI=calculated=for=the=tested=masonró=columns=

Calculation= of= the= potential= energó= for= the= tested= columns= was= carried= out= for= their= resonant=frequenciesK=qhe=modulus=of=the=potential=energó==|bp=EωF|==is=given=bó=equation=ERFI=which=was=derived=from= equations= presented= in= xTzK= qhe= obtained= values= for= the= confined= masonró= columns= were=normalized= to= the= value= calculated= for= the=unconfined= masonró=column= EwF= and=presented= in=cigK= RK=qhe= comparison= of= them= shows= that= confining= of= masonró= column= with= dcom= mesh= bonded= on=

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adhesives=of=different=stiffnessI=causes=reduction=of=column=abilitó=to=absorbing=input=energó=through=potential=energó=bpK=jore=disadvantageous=kind=of=confining=is=using=of=stiff=cement=mortar=adhesive=and= veró= stiff= epoxó= adhesiveI= which= reduce= this= abilitó= to= about= SJU= timesI= whereas= more=advantageous= from= the= analózed= cases= is= confining= with= adhesives= made= of= polómers= mq= and= mpI=which=reduced=this=abilitó=about=onló=O=timesK==

PK4K aamping energy of tested specimens aamping= energó=bd= is= proportional= to=the=damping=coefficient= xI= which= was=determined= for= the=tested=specimens=using=the=halfJpower=bandwidth=method=for= the=dominant=resonant=frequenciesK=qhis=method=uses=the=compliance=function=AEwF=presented=in=cigK=4K=qhe=damping=coefficients=x=were=calculated=from=equation=ESFI=using=the=compliance=function=diagrams=of=tested=columnsK=qhe=values=of=Dw=correspond=to=the=widths=of=the=compliance=curvesI=measured=at=the=amplitude=levels=equal=to=the=maximum=amplitudes=at= the= resonant= frequencies= wr= divided= bó= ÖOK= qo= compare= damping= properties= of= tested= masonró=columnsI=the=obtained=values=of=the=damping=coefficient=x=determined=for=the=confined=masonró=columns=were= normalized= to= the= value= calculated= for= the= unconfined= masonró= column= EwFK= As= previouslóI= the=confinement= reduces= damping= properties= of= masonró= columnsK= qhe= most= disadvantageous= is= using= of=cement=mortar=adhesiveI=which=reduces=damping=energó=almost=R=timesI=whereas=the=most=advantageous=is=using=of=polómer=mq=adhesiveI=which=reduces=damping=energó=about=NIR=times=EcigK=RFK=====PKRK Comments on dynamic properties of confinement ft= should= be= underlined= that= confining= of= masonró= columns= is= disadvantageous= from= the= dónamic=response=point=of=view=Ein=the=elastic=range=of=vibrationFK=qhe=increase=of=internal=forces= in=confined=masonró=columnsI=caused=bó=increase=of=dónamic=responseI=is=equalized=bó=higher=strength=properties=of= the= strengthened= column=crossJsection= in= comparison= to= the=unconfined= columnK= qhe=carried=out=dónamic= testsI= on= masonró= columns= confined= with= dcom= mesh= bonded= on= adhesives= of= different=stiffness= showed= that= applóing= flexible= adhesives= is= more= advantageous= than= stiff= onesK= ft= is= validI=when=the=structure=response=to=a=dónamic=excitation=working=in=the=elastic=range=of=vibrationK=motential=energó=as= well= as=damping= energó=receives= higher= values= in= the= case= of= flexible=polómer= adhesives=than=in=the=case=of=stiff=adhesivesK==

=4K pTATfC ClMmobppflk TbpT lc MAplkov ClirMkp

4KNK Test description qhe= tested= dónamicalló= masonró= columns= were= compressed= up= to= failure= under= static= loadK= qhe=research= was= carried= out= at= Cracow= rniversitó= of= qechnologóI= using= the= universal= testing= machine=wwick=wSMMMI=which=is=able=to=generate=the=compression=load=of=SMMM=kk=Ecig=SFK=qhe=compression=tests= of= all= masonró= columns= were= realized= with= constant= displacement= ratio= of= MKR= mmLminK= qhe=obtained=stressJstrain=curves=are=presented=in=cigK=SK==

= == =

cigK S=rniversal=testing=machine=wwick=wSMMM=EleftFI=view=of=the=tested=confined=masonró=column=EmiddleF=and=the=stressJstrain=diagram=presenting=comparison=of=results=obtained=for=five=tested=specimens=ErightF==

4KOK ptatic compression test results qheir= comparison= indicates= that= strengthening=characteristic= of= the= masonró= columnI= after= confining=them=with=four= laóers=of=dcom= meshI= is= dependent= on=a= kind=of= adhesive= laóerK= qhe=more= flexible=

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=

NUTM=

adhesive= EcompK= the= voung= module= and= the= ultimate= strains= of= the= applied= adhesivesF= the= higher=strength=and=the=column=stiffness=areK=qhe=scale=of=strength=increase=represents=the=comparison=of=the=obtained=maximum=stressI=normalized=to=the=stress=value=of=the=unconfined=column=EwFK=ft=confirms=the=previous=conclusion=that=the=highest=strength=EcigK=TF=was=obtained=for=the=most= flexible=polómer=mp=adhesives= Ew|p|mpF=and=the= lowest=one=for= the=most= stiff= cement= mortar= adhesive=Ew|p|wFK=pimilar=observations=were=found=during=comparison=of=the=damage=energó=Eproportional=to=the=area=measured=under= the= stressJstrain= curves= up= to= the= maximum= stressFK= qheir= valuesI= normalized= to= the= damage=energó=value=of=the=unconfined=column=EwFI=are=compared=in=cigK=TK==

1,00

1,61

1,12

1,41

1,90

M,M

M,2

M,4

M,S

M,8

N,M

N,2

N,4

N,S

N,8

2,M

Z Z_p_mq Z_p_Z Z_p_PM Z_p_mp

Maximum stress normalized x-z

====

1,00

2,001,73

2,27

3,39

M,M

M,R

N,M

N,R

2,M

2,R

P,M

P,R

4,M

Z Z_p_mq Z_p_Z Z_p_PM Z_p_mp

aamage energy normalized x-z

=

cigK T=Comparison=of=the=values=of=maximum=stress=and=of=the=damage=energóI=normalized=to=the=values=obtained=for=unconfined=column=

=qhe= global= strength= increase= of= the= tested= column= is= not= so= high= after= confinementI= because= the=masonró=columns=were=made=of= the=_onarka=bricks=of=high=strength=and=the=glass=mesh=confinement=was=not=so=strongK=puch=disproportion=was=designed=to=emphasis= the= influence=of= the=adhesive= laóer=properties=on=failure=process=of=glass=fibersK=qhese=both=materials=are=of=brittle=characteristic=and=are=vulnerable=to=stress=concentration=phenomenon=xSzK=rsuallóI=the=increase=of=the=masonró=columns=after=confinement=is=higher=EOJP=times=–=after=xRzF=if=bricks=of=lower=strength=and=com=composites=of=higher=strength=are=taken=into=cooperationK===4KPK ptress concentration generated by sharp pieces of bricks fn= the= case= of= nonlinear= deformations= of= confined= masonró= columnsI= absorption= bó= irreversible=hósteretic= energó= bh= is= activatedI= when= internal= damage= of= masonró= column= occursK= qhe= structure=abilitó= to= absorb= deformation= energó= increases= considerabló= in= this= stateI= because= the= confinement=protects=the=inner=vertical=cracks=of=masonró=column=against=expansionI=also=increasing=ductilitó=and=global= strength= of= the= columnK= rnfortunatelóI= the= broken=and= sharp= pieces= of= masonróI= acts= on= the=brittle=confinement=structure=from=inside=and=stress=concentrations=cause=damage=of=com=fibersK=fn=the=case=of= the=masonró=columns=of=rectangular=crossJsectionI=the=highest=stresses=concentrate=in=cornersI=causing=failure=modes=presented=for=the=tested=specimens=in=cigK=UK=qhe=failure=mode=of=columns=with=stiff= and= flexible= adhesive= is= similar= EcigK= VFI= but= the= flexible= adhesives= Ewithstanding= of= large=deformationsF=protects=the=com=fibers=against=damage=more=efficientló=than=the=brittle=stiff=adhesivesK===

= = = = = == w= w|p|mq= w|p|w= w|p|PM= w|p|mp=

cigK U=cailure=modes=of=the=tested=masonró=columns=

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=

NUTN=

= =

cigK V=woom=of=the=confinement=failure=mode=located=in=the=column=cornersW=flexible=adhesive=Ew|p|mqF=–=left=and=stiff=adhesive=Ew|p|PMF=–=right=

=qhe=mechanism=of=stress=concentration=reduction=bó=flexible=adhesive=Ein=contact=with=com=compositeF=was=described=in=xNMzK=ft=is=known=xNNz=that=shear=and=normal=stress=concentrations=appear=in=adhesive=and=com=composite=in=the=place=of=crack=occurrenceI=also=in=the=case=of=masonró=column=EcigK=NMFK= ff=the=adhesive=is=brittle=and=stiff= EepoxóI=cement=mortarFI= the=crack=propagates= through=it= immediateló=EcigK=NMbFI=generating=high=stress=directló=to=com=compositeK=fn=the=case=of=flexible=adhesive=Epolómer=mq=and=mpFI= the=same=load=level=does=not=cause=propagation=of= the=crack=through=polómer=adhesiveI=which=dissipates=energó=at=the=crack=tip=bó=ductile=deformation=EcigK=NMcFK=qhis=mechanism=protected=the=dcom=meshI=resulted=in=higher=strength=of=the=specimens=with=the=flexible=adhesivesK==

=crack

=========

==

Concrete prism Etension zoneF

^dhesive

Ccom laminate

aF bF cF

Masonry column

^dhesive

dcom mesh =

cigK U=pcheme=of=crack=propagation=through=adhesive=laóers=Ecaused=bó=stress=concentrationFW=EbF=brittle=and=stiff=EepoxóI=cement=mortarFI=EcF=flexible=Epolómer=mq=and=mpF=

=RK ClkCirpflkp =qhe=technologó=of=confining=using=flexible=polómer=adhesives=is=an=innovative=methodI=proposed=for=application= in= strengthening= of= masonró= columns= with= com= compositesK= qwo= kinds= of= polómer=adhesives= made= of= polóurethane= mass= were= applied= for= bonding= of= the= dcom= mesh= to= masonró=columns=tested=under=dónamic=and=static=loadsK=pimilar=ones=were=testedI=applóing=two=kinds=of=stiff=adhesivesK=qhe=comparison=of=results=obtained=for=specimens=with=stiff=Eepoxó=and=cement=mortarF=and=flexible=Epolómer=mq=and=mpF=adhesives=showed=that=the=use=of=flexible=adhesives=in=confiningI=reduces=stress= concentrationsI= better= protecting= com= composites= and= causing= an= increase= of= strength= of= the=confined=masonró=columnsI=than=stiff=and=brittle=adhesivesK==qhe=dónamic=tests=carried=out=allowed=presenting=dónamic=effectiveness=of=various=tópes=of=adhesives=in=case=of=confining=application=in=earthquake=protectionK=qhe=obtained=results=indicate=that=applóing=flexible= adhesives= is= more= advantageous= than= stiff= onesI= when= the= structure= response= to= dónamic=excitationI= working= in= the= elastic= range= of= vibrationK= ft= was= observed= in= the= cases= of= damping= and=potential= energó= Epossible= to= absorb= bó= the=confined= masonró= columnFK= eistorical= masonries= would=take=advantage=of=the=flexible=bondingI=but=the=durabilitó=aspect=has=to=be=investigatedK===AChkltibadbMbkTp =qhe=research=presented=in=the=paper=has=been=developed=within=the=grant=koK=k=kRMS=MTN4PUK=

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=

NUTO=

obcbobkCbp xNz Aiello= jKAKI= jicelli= cKI= salente=iK= EOMMTF= ptructural= upgrading= of= masonró= columns= bó= using=

composite=reinforcementsK=ApCb gournal of Composites for Construction=NNESFW=SRMJSRUK==xOz Aiello=jKAKI=jicelli=cKI=salente=iK=EOMMVF=com=Confinement=of=pquare=jasonró=ColumnsK=ApCb

gournal of Composites for Construction=NPEOFW=N4UJNRUK==xPz Corradi= jKI= drazini= AKI= _orri= AK= EOMMTF= Confinement= of= brick= masonró= columns= with= Ccom=

materialsK=Composites pcience and Technology=STW=NTTOJNTUPK=x4z _orri= AKI= Corradi= jK= EOMMVF= Confinamento= di= pilastri= in= muratura= tramite= compositi= con= fibre=

metallicheK= fnW= mrocK ConfK juoiCoP jechanics of masonry structures strengthened with composite materials=seniceI=AfClI=NO4JNPNK==

xRz a’Ambra= CKI=ai=iudovico=jKI= _alsamo=AKI= mrota=AKI=janfredi=dK= EOMMVF=Confinement= of= tuff=and=brick=masonró=columns=with=com=laminatesK=fnW=mrocK ConfK juoiCoP jechanics of masonry structures strengthened with composite materials=seniceI=AfClI=OPOJO4NK==

xSz hwiecień= AK= EOMMVF= molómer= flexible= joint= –= an= innovative= repair= sóstem= protecting= cracked=masonries=against=stress=concentrationsK=fnW=mrocK ConfK molefTbCe’M9 mrotection of eistorical Buildings=oomeI=CoC=mressI=_alkemaK=

xTz hwiecień=AK=EOMNNF=clexible=polómer=adhesives=versus=stiff=mineral=and=epoxó=adhesives=tested=dónamicalló= on= masonró= columns= strengthened= using= of= bonded= dcom= meshK= fnW= mrocK Uth fnternational Conference on ptructural aynamics brolavk OMNN=ieuvenK=

xUz bk=VVUJO=EOMM4F=ppecification=for=mortar=for=masonró=–=jasonró=mortarK=xVz hwiecień=AKI=wając=_K=EOMMUF=aónamic=response=of=the=cracked=masonró=building=repaired=with=

the= clexible= goint= jethod= –= an= innovative= earthquake= protectionK= fnW= mrocK Tth fnternational Conference of bApa brolavk’OMMU=pouthamptonK=

xNMz aerkowski= tKI= hwiecień= AKI= wając= _K= EOMNNF= Ccom= strengthening= of= bent= oC= elements= using=stiff= and= flexible= adhesivesK= fnW= mrocK Tth fnternational Conference AjCj’OMNN Analytical jodels and kew Concepts in Concrete and ptructures=hrakówK=

xNNz _uóukozturk=lKI=dunes=lKI=haraca=bK=EOMM4F=mrogress=on=understanding=debonding=problems=in=reinforced= concrete= and= steel= members= strengthened= using= com= compositesK= Construction and Building jaterials NUW=VJNVK=


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