~dldl: df ClCrJch: c Tcmclop Unlftnld.ulc de Cl:m!1n .

aostracts @f the intQrrnational w<i>rkshop

fr@m materials m@delling to strwCi:tu rral J;)@Jiformcamc:e

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Faculdade de C iellcias e Tccn()I()~ia da li llil'ersidade de C"imhra

International I'ederation for Structural Concrete

Abstracts of the

International Workshop

"Fire Design of Concrete Structures -From Materials Modelling to Structural Performance"

University of Coimbra, Portugal

Slh and glh of November 2007

o Joao Paulo Rodrigues (Chairman) - Univ. Coimbra • Portugal

o Luc Taerwe (Co - Chairman) • (Convener fib WP 4.3.2) - Ghent University - Belgium

o Niels Peter Hoj (Convener fib TG 4.3) - HOJ Consulting GmbH - Switzerland

o Gabriel Khoury (Convener fib WP 4.3.1) - Imperial College of London - UK

o Pietro G. Gambarova - Politecnico di Milano - Italy

o Alberto Meda - University of Bergamo - Italy

o Fernando Jose F. Branco - University of Coimbra - Portugal

o Aldina Maria C. Santiago' University of Coimbra - Portugal

o Adelino Vasconcelos Lopes - University of Coimbra - Portugal

o Sandra Raquel S. Monteiro- University of Coimbra - Portugal

o Alberto Meda - University of Bergamo - Italy

o Angel Arteaga - Instituto Eduardo Torroja - Spain

) 0 Antonio Le~a Coelho - LNEC - Portugal

o Arnold Van Acker - Belgium o Arnoud Breunese - TNO - The Netherlands

o Carmelio Majorana - University of Padua - Italy

o Ekkehard Richter - Tech. Univ. of Braunschweig - Germany

o Fabienne Robert - CERIB - France o Gabriel Alexander Khoury - Imperial College of London· UK

o Jean-Claude Dotreppe - University of Liege - Belgium

o Jean-Fran~ois Deno<i! - FEBELCEM - Belgium

o Jean-Marc Franssen- University of Liege - Belgium

o Jesus Rohena - FHWA - USA

o Joao Paulo Rodrigues - University of Coimbra - Portugal

o Joaquim Barros - University of Minho - Portugal

o Jose Maria Izquierdo - Intemac - Spain o Josko Dzbolt- University of Stuttgart - Germany

o Kese Both - TNO - The Netherlands

o Long Phan - NIST - USA

o Luc Taerwe - Ghent University - Belgium o Mamoud Behloul - Lafarge - France

o Paolo Riva - University of Brescia - Italy

o Patrick Bamonte - Politecnico di Milano - Italy

o Pietro Gambarova- Politecnico di Milano - Italy

o Roberto Felicetti - Politecnico di Milano - Italy o Sergio Lopes - University of Coimbra - Portugal

o Steward Matthews - BRE - UK

o Tom Lennon - BRE- UK

o Ulia-Maija Jumppanen - Finland

o Ulrich Diederichs - University of Rostock - Germany

o Xianyu Jin - Zhejiang University- China

o Yngve Anderberg - Fire Safety Design AB . Sweden

o Yoshikazu Dta - Ota Engineering - Japan

o Zongjin Li - Hong Kong Univ. of Science and Tech. - China

fib Workshop " Fi ~e Design of Concrete Structures -From Materials Modelling to Structural Performance" - Coimbra 2007

PROGRAM 1st Dav· Mornina

Bh-Bh 30m REGISTRATION Bh 30m - Bh 45m OPENING SESSION

Bh45m-9h Luis S. Silva - Vice President of FCTUC - "UNIVERSITY OF COIMBRA, ITS LIFE AND RESEARCH IN FIRE SAFETY OF STRUCTURES"

9h-9h 30m KEYNOTE SESSION 1 - Gallriel Ktloury -Imperial College of London - UK -"FROM MATERIALS BEHAVI0UR TO APPLICATION"

9h 30m - 9h 40m Pierre Pimlenta - Centre Scientifique et Technique du Batiment - France-

"EXPERIMENTAL STUDY OF MECHANICAL BEHAVIOUR OF HIGH PERFORMANCE CONCRETES AT HIGH TEMPERATURE"

Ulrich Diederichs - Universltilt Rostock - Germany -9h 40m -9h 50m "EXPERIMENTAL INVESTIGATIONS CONCERNING HIGH TEMPERATURE

BEHAVIOR OF ULTRA HIGH STRENGTH CONCRETE"

) 9h 50m-l0h

Takeo Hirashima - Chiba University - Japan -"COMPRESSION TESTS OF HIGH-5TRENGTH CONCRETE CYLINDER AT

ELEVATED TEMPERATURE" Pietro Gambarova • Polltecnico di Milano - Italy -

10h -10h 10m "HIGH·TEMPERATURE RESISTANCE AND THERMAL PROPERTIES OF SELF· COMPACTING CONCRETE"

Cruz Alonso· Inst. of Construction Science, Eduardo Torroja - Spain . 10h 10m-l0h 20m "DEHYDRATION AND REHYDRATION PROCESSES IN CEMENTITIOUS

MATERIALS AFTER FIRE. CORRELATION BETWEEN MICRO AND MACROSTRUCTURAL TRANSFORMATIONS"

10h 20m-l0h 40m IDiscussi6'n 10h 40m -llh 6..,§) FcFcEE [BREAK

KEYNOTE SESSION 2 - Carmelo Majorana - University of Padua - Italy -llh -llh 30m "MICRO-5TRUCTURAL MODELLING OF CONCRETE UNDER FIRE

CONDITIONS " F. Pesavento· University of Padua - Italy-

llh 30m-llh40m "TOWARDS PREDICTION OF THE THERMAL SPALLING RISK THROUGH A MULTI·PHASE POROUS MEDIA MODEL OF CONCRETE"

Masatoshl Tokoyoda • Japan Testing Center for Construction Materials - Japan llh40m-llh50m -

"AN EXPERIMENTAL STUDY OF TRANSIENT STRAIN FOR A CONCRETE ) WITH LIMESTONE AGGREGATE"

B.B.G. Loltman • Delft University of Technology - Holland-llh 50m - 12h "A MODEL FOR THE STRUCTURAL BEHAVIOUR OF BORED TUNNELS

DURING FIRE" 12h -12h 10m Xinmeng Yu - University of Sheffield· UK · "MODELLING LOCALIZED FAILURE

OF REINFORCED CONCRETE SLABS IN FIRE" 12h 10m -12h 20m Sven Huismann- Federal Institute for Materials Research and Testing· Germany·

' DAMAGE AND STRENGTH REDUCTION OF HIGH PERFORMANCE CONCRETE DUE TO THERMOMECHANICAL STRESSES"

12h 20m - 12h 30m Roberto Felicetti - Politecnico de Milano - Italy -"ASSESSMENT OF THE EQUIVALENT THERMAL DIFFUSIVITY FOR FIRE

ANALYSIS OF CONCRETE STRUCTURES" 12h 30m-13h Discussion 13h -14h 30m LUNCH

/ / J

/

/

1"' Day· Afternoon j KEYNOTE SESSION 3 - Ulrich Schneider - Technical Univ. of Vienna - Austria-14h 30m -1Sh "EXPLOSIVE SPALLING OF CONCRETE UNDER FIRE CONDITIONS" d-Ou-:J

Robert Jansson· SP Technical Research Institute - Sweden - "EXPERIMENTAL

t/ 1Sh -1Sh 10m STUDY OF THE INFLUENCE OF POLYPROPYLENE FIBRES ON MATERIAL PROPERTIES AND FIRE SPALLING OF CONCRETE"

/ Takashi Horiguchi- Hokkaido University - Japan- "EXPLOSIVE SPALLING 1Sh 10m-1Sh 20m MITIGATION MECHANISM OF FIBER REINFORCED HIGH STRENGTH

CONCRETE UNDER HIGH TEMPERATURE CONDITION"

Zhaohui Huang - University of Sheffield, UK-

~ 1Sh 20m -1Sh 30m "EFFECTS OF SPALLING ON THE BEHAVIOUR OF REINFORCED CONCRETE STRUCTURES IN FIRE"

)

1Sh 30m -1Sh 40m Gabriel Khoury - Imperial College of London - UK - "POLYPROPYLENE FIBRES ;t;.~Ic:: uw AND EXPLOSIVE SPALLING" Jean-Christophe Mindeguia. Centre Scientifique et Technique du Batiment- ~

1Sh 40m-1Sh SOm France- if "EXPERIMENTAL STUDY OF FIRE BEHAVIOUR OF DIFFERENT CONCRETES et.57Ct'/

- THERMO-HYDRAL AND SPALLING ANALYSIS" ~c>r/wAi ~IJA- (VO c:

Josko Oibolt - , University of Stuttgart - Germany-

\/ 1Sh SOm -1Sh "NUMERICAL ANAL YSYS OF SPALLING OF CONCRETE COVER AT HIGH TEMPERATURES'

1Sh -16h 20m I!)iscussiotl) 1Sh 20m -16h 40m C0FFEE BREAK / KEYNOTE SESSION 4 - Luc Taerwe - Ghent University - Belgium - ' FROM 1Sh 40m-17h 10m MEMBER DESIGN TO GLOBAL STRUCTURAL BEHAVIOUR"

/ Mark A Bradford - The University of New South Wales - Australia-17h 10m -17h 20m "NONLINEAR ANALYSIS OF SHALLOW PARABOLIC CONCRETE ARCHES

)

UNDER THERMAL LOADING"

/ ,~ Miguel Gon~alves - University of Porto - Portugal- "A SIMPLIFIED METHOD 17h 20m -17h 30m FOR THE DETERMINATION OF THE ULTIMATE BENDING CAPACITY OF

REINFORCED CONCRETE BEAM SECTIONS AT HIGH TEMPERATURES"

lIaria Venanzi - University of Perugia, Italy -17h 30m-17h 40m "ANALYTICAL SAFETY ASSESSMENT OF R.C. FRAMES EXPOSED TO FIRE"

Shan-Shan Huang- University of Sheffield- UK - A· 17h 40m -17h SOm ''THE BUCKLING OF SLENDER CONCRETE AND CONCRETE-FILLED

/ COLUMNS IN FIRE" 18 Glntarls Kaklauskas- Vilnius Gedlmlnas Technical University - Lithuania-

17h SOm-18h "LAYERED SECTION ANALYSIS OF RC SLABS SUBJECTED TO FIRE"

Alexandre Landesmann - Federal University of Rio de Janeiro, Brasil-

/ 18h -1Sh 10m "PLASTIC-HINGE APPROACH FOR PERFORMANCE-BASED ASSESSMENT OF RC COLUMNS UNDER FIRE"

1Sh 10m-18h 30m Discussion 20h ~@NFERENeEII!)INNER

) ILK tt~l""\ln..

CiJZ Io,,-() mfWl \ t;ivT

~r 1)\({'Yf:t 8h 30m -9h

~fc-;' 9h-9h10m

I "'~

~~( 9h 10m - 9h 20m

SoiL ~

~(/D£bmiJ. 9~~~'\l.irilr 30m,/

~a\ ~aJ f!~" 'Mrf /

9h 30m - 9h 40m

) 9h 4Om- 9h sam

9h SOm -10h

10h -10h 10m

10h 10m -10h 30m

10h 30m -10h SOm

10h SOm-11h 20m

11h 20m -11h 30m

11h 30m -11h 40m

)

11h 40m-11h Sam

11h SOm-12h

~~~ 12h -12h 10m

12h 10m-12h 20m

12h 20m-12h 30m

12h 30m-13h

13h-14h30m

2iiODay - Morning SESSION 5 - Chair - Luc Taerwe, Co-chair - Fernando Branco

KEYNOTE SESSI0N 5 - Venkatesh Kodur - Michigan State University - USA-"MACROSCOPIC FINITE ELEMENT MODELS FOR TRACING THE RESPONSE

OF CONCRETE STRUCTURES UNDER FIRE CONDITIONS"

Takashl Horlguchi - Hokkaldo University, Japan- 'BENDING STRENGTH AND FRACTURE TOUGHNESS OF HYBRID FIBRE REINFORCED HIGH STRENGTH

CONCRETE AT HIGH TEMPERATURE"

Yahia Msaad - CERIB - Study and Research Center for the Concrete Industry -France - "TEMPERATURE AND SHEAR CAPACITY CALCULATION FOR PRESTRESSED HOLLOW CORE SLABS UNDER FIRE CONDITIONS"

1.11.,"'4 teu:n6nl Jean-Marc Franssen - University of Liege - Belgium -"NUM@ICAL EVALUATION OF THE FIRE BEHAVIOUR OF A CONC~ETE

?liP TUNNEL INTEGRATING THE EFFECTS OF SPALLING" ~b'"""c,,- I

Patrick Bamonte - Polilecnico di Milano - ltaly-"ON THE EFFECTS OF STRUCTURAL STABILITY ON THE M-N ENVELOPES

OF THERMALLY-DAMAGED RIC SECTIONS" Claudio Pozzi - Ove Arup & Partners - UK -

"A NEW RISK-BASED APPROACH TO PREDICT SPALLING OF ORDINARY STRENGTH CONCRETE WALLS SUBJECTED TO FIRE"

Frank Dehn "Leipzig Institute for Materials Research and Testing- Germany-"INFLUENCE OF TYPE AND AGE OF SYNTHETIC FIBRES ON THE HIGH

TEMPERATURE AND FIRE BEHAVIOUR OF CEMENTITIOUS MATERIALS"

Martin Schneider- Technical University of Vienna - Austria- "COMPARISON OF AN APPROXIMATED METHOD WITH FEM CALCULATIONS FOR THE EVALUATION OF THE FIRE RESISTANCE OF CONCRETE TUNNEL

SECTIONS"

Ji)iscusil5n C0FFEEI B_REAK

KEYNOTE SESSION 6 - Stephen Pesslki - Lehigh University - USA -"CURRRENT RESEARCH NEEDS FOR THE FIRE DESIGN OF PRECAST

CONCRETE Bl!.IlLDING STRUeTURES INI U.S. PRACTICE"

Long Phan - National Institute of Standards and Technology - USA-"PERFORMANCE OF CONCRETE IN FIRE"

Joao Paulo Rodrigues - Universidade de Coimbra - Portugal "BEHAVIOUR OF A FIBRE REINFORCED CONCRETE TUNNEL SEGMENTS

SUBMITTED TO FIRE" Jeremy Chang - University of Canterbury - New Zealand

"EFFECT OF THE END AND SIDE CONNECTIONS TO THE HOLLOWCORE CONCRETE FLOORING SYSTEMS IN FIRE"

Fernando G. Branco" Universidade de Coimbra - Portugal "INFLUENCE OF THE TEMPERATURE ON THE STRENGTH OF SINGLE

ADHESIVE ANCHORS UNDER TENSILE LOAD" Paulo Pilato" Polytechnic Institute of Bragan<;a - Portugal -

"PUSH-OUT TESTS FOR PARTIALLY ENCASED BEAMS AT ELEVATED TEMPERATURE"

Brian Hardie - Ulster University- UK-"EFFECTS OF ELEVATED TEMPERATURES ON PROPERTIES CONCRETE

BLOCKS" Ali Nadjai - University of Ulster - UK- "IS A FRP-RC STRUCTURE SAFE

ENOUGH IN FIRE?"

Discussion LUNCH

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V 14h 30m-15h i

"RECENT ADVANCES AND RESEARCH NEEDS IN THE ASSESSMENT OF FIRE DAMAGED CONCRETE STRUC;ruRES"

Pf

Pi/v'

"PROPERTIES FOR THE ASSESSMENT OF THE RESIDUAL STRENGTH OF

t~::-~:-.:::j _____ A~~C~ONCRETE 7XPOSED TO FIRE"

15h 10m -15h 20m "REPAIR OF FIRE DAMAGED RIC BEAMS WITH HIGH PERFORMANCE FIBER REINFORCED CONCRETE JACKET"

15h 20m -15h 30m "EXPERIMENTAL STUDY ON TRIAXIAL BEHAVIOUR OF CONCRETE AFTER EXPOSURE TO HIGH TEMPERATURE"

I

DAMAGE IN HIGH·STRENGTH MORTAR MIXED POLYPROPYLENE FIBERS

h~~--=--=--l-______ --.:B=-Y.:...::U=-L T:..:RA..:: SONIC TOMOGRAPHY"

Lars • SP Technical Research Institute - Sweden-"OVERVIEW OF FIRE TESTING OF CONCRETE AND CONCRETE

PROTECTION SYSTEMS FOR TUNNELS IN SWEDEN"

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PUSH-OUT TESTS FOR PARTLULY ENCASED BEA.MS AT ELEVATED TEMPERATVRE

P'l P A G I' Ra G :".. " B' M' ; . L ' 4 Iota .. "'-. . ; mas aylliU.L _"- . : 1 esqrnta. LM.R. : Barre1r.l. U15a

1 Poly. Inst. of Bragan, a, Campll;, S. Apolonia, 5301 Bragan~a, PortugaL ppilotorGJipb.pt 'Uni\'. ofSalamanea. Avda. Cardenal Cisneros, 34, 49022 Zamora. Spain. aramosOVusaLes l Poly. Insr. ofBragan,a. eampm S. Apolonia. 5301 Bragan,a, Portugal. Imesguita@ipb.pt 4 Poly. Insr. of Braganr;a, CampllS S. Apolonia, 5301 Braganr;a, PormgaL IbarreirarGJipb.pt

Keywords: Elevated temperatures. bond sIrength, pariially encased beams.

LXTL'IDED ABSTRACT

Partially encased beam is a steel-concrete composite siIUCture, made-up wiill a hal rolled profile and filled with concrete benveen flange;,. Such sIrllchlfal eiemem improves load­bearing capacity at elevated temperattIres.

Bond SIress is ille key parameter ro determine the S1rength 1iroit state in splitting comact, being represented by the shear SIress at steel-concrete interface. which enables both materials to gel composite mechanical action, see figure 1.

Figtlfe 1 - Model for partially encased beam at elevated temperarure.

Tltis work presents an experinlental method for testing bond clLlfacteristics for partially encased beams at elevated temperamre (400 ['C]). which will be ltseful for the numerical modelling of contact. Contact may be represented by 11011 linear fioite spring element introducing force yersus relati"e c1isplacemem berween both materials. u.,illg geometnc and lllarenainou linear analysis_

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The experimental principle is based on axially load concrete blocks by mea1lS of a hydraulic jack, at high temperatme level measuring the rel.nye displacement of concrete, determining elle load histogram. A set of three lests were carried am for partially encased beams witham welded stirrups.

Specimens were heated at constant heating rate of 400 [OOh], by means of electro - ceramic resistances. using 70 [kVA] heating power unit. as represemed in figure 2. Thenuocouples (~pe K) were used to control heating source and to record temperalure inside eight speciiic point, over each partially encased beam (four welded on 'teel beam and four plated connected to concrete, see figure 3).

E:'I"';mr:utal tnt c) Testiug model Figure ~ - E.:perimemal set-up for push Ollt tests at elevated temperature.

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Figure 3 - Thermocouple po,inon on each tested partIally encased bearlL

E\'ery material was characterized accorchug to natIOnal srandards [1.2]. Hot rolled profile S275. with 500 [1\IPa] Yield stress auello1\' strengrh re1l1forced concrete eLY!5. with 0=8 [mlll] B500 bars with rib,. StirruPI are mac", of cold fanned sloel with 4 [Illlll] diameter plain bars Wilh -:00 [lvJPa] )~e1d sire",. lee figure 1.

)

Steel .urface roughness characterization was determined according to ISO st:lndards [3]. Roughness was Illeasured over 18 evaluation lengths for each beam. producing an average rouglUless of3.12 U-IUl].

After temperamre is stabilized imide beam cross sec lion. an axial load was introduced and incremellted in several steps up to the ultimate limit state of coucrete blocks (large longimdinnl displacement wirh local concrete failure), see figure 4.

All recorded temperamres presenr values benveeu 350 ['C] and 400 ['C] , being the steel­concrere imerface controlled with Ihemlocouples WTS2, PTC2 and PTC3.

test. Figure 4 - Pnsh ou! tesIS for partiall)' encased beams at 400 ['C].

Figure 5 represents the experimental results for alltheee beams. using natural adherence al high Iemperarure. Displacement wa.' measured by means of wire porenriometer sensor anached to the COllcrele blocks widl all accuracy of 0.1 [mlll].

J,,,..rJ~t _1'ulIln --11.1,,,,11 _I~,ml: 11111:11 .--...:.::...:.::-.- --- ---.- ---.•

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b) T ';:l!lper.mtr~ dunng h;atiug procc-;:> a:ld during rueclJ.illllcalloildiug at r!l~nnal ste<ldy SIOle cond.dcll:i.

Figure 5 - Reml!; for beams wiill nanlfal adherence al ~OO ['('].

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The maxilllum shear stress was detemuned at 400 ['C] for all tests. Differences between force displacement behaviour resuirs for the fir;t two tested beams may be justified by the fact that in the first case both conerete blocks travel at dle same time, while in the second case, (beam 11) presents local failure in one block, followed by large conerele displacement. The third test followed measured force displacemem of the first lest with higher maxintum shear stress, see table 1.

Table 1 -Ex erimenlal .-alues for bond stress at 400 ['Cl. TESTED BE."l,! WL'1MU;'{ ;'l"-"'ill.-[u"{

BeallllO Beam 11 Beam 12

FORCE [1'11 BOND STRESS [MP,] 44141 45-lS7 71689

0.293 0302 0.476

The shape of this result agrees with t)pical bond characteristics for composite sections presented at room temperature, [4]. ntis shape also agrees wiill push-out tests recorded at room temperature, [5].

More results are being produced for partially encased beams, at eleyated temperature, using stirmps welded to the web steel profile. Different resuits are expected for bond stress and bond behaviour.

Referenres: [1] NP EN 10002-1, -Iv!emilic materials. Tensile testing. P21t 1: IVlethod of test (at ambient

temperamrer-; 1990. [:2] NP EN 12390 - 3. "Testing hardened concrete. Part 3: Compressive strength of test

specirnerls". 2003. [3] ICS, ISO 4288, ""Geometrical product specification (GPS)" - surface te:-:tl.lre: Profrle

method - mles ane! procedures for the assessmeur of surface texture. Switzerland, 1996. [4] Romulo Danilli da Sil\"a. ""E'mdo da aderencia a~o concreto em pilares nUstos

preenchidos": (in Pomrglle,e). Master of Science dre,is. Sao Jorge School of Engineering, Uruver,iry of Sao Paulo, Brasil. IvIarch 2006.

[5] Ramos Gavilan, A.B.: Pilato. P.A.G.: ivlesql.lita. L.IvIR.: "Esmdio del contacto entre perfil metallco y hormigon en vi!,!a, menilicas parcialmenre embebidas": (in Spanish), proceedings of Numerical Methods in Engineering: CMNE!CII..AJ:VlCE 2007. Porto, 13 -15 Jnne. 1007.