Temperature analysis and validation of partially encased beams submitted to elevated temperature

(1)

(2)

(3)

This Inlernational Congress was organized by: GIDA1-Fire Salety -Research and Technology UNIVERSIDAD DE CANTABRIA

Dpto. de Transportes y Tecnologia de Proyectos y Procesos Aveia. Los Castros, s/n

39005 Sanlander. Spain

n.

+ 34 942 201826. Fax. +34 942 202276; [email protected]; hllp:/Aw/W.gidai.unican.es

With the collaboration of: Society of Fire Proteclion

Engineers SFPE

National Fire Proleclion Association

NFPA

Inlemalional Associalion for Fire Safely Science

IAFSS Scientific Committee - Editorial Board:

Dr. Orlando Abreu .... . Dr. Daniel Alvear .... . Dr. Vylenis Babrau:.kas Dr. Jorge A Capote Dr. Wan·Ki Chow Dr. Pedro J. M. Coelho Dr. ~1jchael Delichatsios Dr. Nlck Oembsey ... _ ... Dr. Bogdan Dlugogorski Dr. Sergey Dorofeev Dr. Dougal Drysdale Dr. Carlos Femândez·Pello Dr. Charles M. Flefschrnarm .. _ Dr. Pedro L. Garcia Ybarra ... . Dr. S!eve Gwynne ... . Dr. George HadjisophocIeous Dr. Yup Hasemi.. .. _ ... _._ ... Mr. Morgan Hurley .. Dr. Marc L. Janssens ... _ .. Dr. Frar.dsco J. Jimênez·Peris Dr. Grunde Jomaas .. _._ Dr. Timo Korhonen ... . Dr. Chrlstopher W. Lautenberger .. Dr. Mariaoo lázaro Dr. Gregory T.linleris ... . Dr. Amab!e lilián... . ... _ ... . Dr. Rlchard E.lyon ... Dr. Andre MarshaU Dr. Julio M. Marti Or. \"Iill~m E. Mel! Dr. Barl Merci.... Or. Frederick W. WoO\'JTer ... Dr. Eugeflio Dnale ... Dr. Richard O. Peacock ... Dr. Paulo Piloto. Dr. David Purser .... Dr. James G. Ouintiere

Dr. Guillenno Rein ... . Dr. StaflÍsIav l. Slol~rov Dr. TakeyoshiTanaka Dr. Josê L Terero ... . Or. Amaud Trouve. Dr. Patrick Var. Hees

Dr. Vittorlo Verda ... . Dr. Domingos X. Viegas .. .

Oro Sergey Vyazovkin ... Dr. Jennifer Wen

Ufliversity olCantabria (SPA) University 01 Cantabria (SPA) Fire Sdence aod Technology Inc. (USA) Universily of Cantabria (SPA) Hong Kong PoIylechnic Ufliversi!y (CHN) IflStitulo Superior Técnico Lisboa (PRD Ufliversity 01 Ulster (UK)

Worcesler PoIylechnic IflSUtule (USA) Universi\y of Newcaslle (AUS) FM Global (USA) University 01 Edinburgh (UK) Universi\y cf Cahfomia (USA) Universi\y 01 Canlerbury (NZL)

National Dfslance Educatior. Universi\y (SPA) Hughes Associates (UK)

Universi\y 01 Carletor. (CAN) Waseda Ufliversi\y (JPN) SFPE lUSA)

Soulhwesl Research lr.stitule (USA) Universily of Cordoba (SPA) iechnical Universi\y 01 Oer.mark (DK) VTT(FI)

Reax Er.gineering (USA) University 01 Car.tabria (SPA) NIST(USA)

Technical Uni~ersi\y 01 Madrtd (ESP) Federal Aviation Administratior. (USA) University of /"o.iarylafld (USA) Technical Uruversity 01 Catalonia{SPA) U.S. Forest SeNice (USA) Gher.t University (BE)

CaHlomia PoIytechnic State Uni~ersity (USA) Technical University 01 Catalon~ (SPA) NIST(USAI

Instituto Politécnico de Bragança (PRT) Hartford Environmental Research (UK) Unlversity of Maryland (USA) Imperial CoIlege (UK) Universi\y 01 Marylafld (USA) Kyoto Universi\y (JPN) Uni~ersity 01 Edinburgh (UK) Uni~ersity of r.iaryland (USA) Lund Universi\y (SWE) PoIitecnico di iorino (liA) Universtty cf Coimbra (PRT)

Universily 01 Alabama aI Birmingham (USA) Kingston'Universi\y (UK)

Spanish SecUon 01

(4)

International Congress

FIRE COMPUTER MODELlNG

UNIVERSIDAD DE CANTABRIA

Opto. de Transportes y Tecnologia de Proyectos y Procesos

GIDAI - Seguridad contra Incendios - Investigación

y

Tecnologia Avda. Los Castras, s/n

(5)

Inlernalional Congress

FIRE COMPUTER

MODELlNG

Editedby:

Jorge A. Capote Daniel Alvear

Compiled by:

Mariano lázaro David Lázaro Virgínia Alonso

Acknowledgements:

Servicio de Publicaciones (Universidad de Canlabria)

FIRE COMPUTER MODEUNG : inlemalional congress, (Sanlander. 19 de Octubre de 2012)1 edited by JOlge A. Capote, Daniel A1vear ; comp~ed by Mariano Lázaro, David lázaro, Virginia Alonso-Sanlander: Universidad de Cantabria, GIDAI, 12012].

0.L. SA-608-20t2 ISBN 978-84-86116-69-9

l.1ncendi05 - Simulacióo

por

Ordenador -Congresos \. Capole Abreu, Jorge A, ed. lil. 11. Alvear Portilla, Daniel, ed.liI. 111. Lázaro Urrutia, Mariano 111. Universidad de Canlabria. Grupo de Invesligación y Oesarrollo de Acluaciones Industriales.

614.84(063)

Prinled: Grcificas Iguna, S.A.

OCOPYRIGHT. AO rights reservado No pal1 cr Ihis book mar be reprinled I)( replOduced or uti!ized in any fonn or by any eleclronic, mechanical, or olher means, now know or hereafter invenled, including pholoc:opying ar recarding, ar il1 any ilfOfTT1ation starage ar relneva! syslem, wilhoul pennission in wnting frem lhe editor.

(6)

97

Sen~itivity analysis of solid degradation mcchani~m with the Arrheniu~ law under inert atnlosphcrc ... . 111

Multi-scale modeling of the thennal decomposition of a fire rcturdant plywood ... . 131

Thennoplustic mass los~ rate prediction at Cone Calorimetcr through a set of parameters obtained by optimization against experimental STA tests ... .. 151

Numcrical Simulation of\Vater Disehargc from Large-Capacity Foam Monitor 161 Numerieal and Experimentallnvestigation oI' Fire Smoke Toxicity ... .. 171

Multi-Scale TccJmique Applicd to the Ventilation Dcsign for Subway Syslems... 189

CFD modeling ofa tunnel tire by thennul eoupling ornuid fiow and struclure... 201

Full Seale Tests and CFD Modeling or a Compartmcnt Fire in an Atrium with Smoke Exhausl... 215

Tempcraturc Anulysis and Vulidution oI' Purtially Eneased Beurns Subrnitted to Elevated T cmperature ... . 235

(7)

Physical Scale and Comput<ltion<ll Modeling of Smokc Mavement in High Spccd Passenger Tr<lins ... .

259

Fire Beh<lviour in Canyons due to SymmetTic and Asymmetric Ignilians ... . 275

Invcstigatiotl afthe Ch<lracteristics ofa Large Planar Space Fire using 3-D CFD Analysis. 287

Estimating Grid EfTects af Slow and Medium Growing Fires in FDS ... 299

Comparisons on Complltational Schcmes Used in CFO Models ... . 315

Parallcl simlllation of automobile interior tire and its sprcad onlo olher vebicles ... . 329

Linearization and grouping of tcmperatures in integrated tire dcsign using adv<lnced struclural <lnalysis ... . 339

Non-Stoichiometric Fire Modcling Predietions witb Applications la Train Fires in Tunnels ... . 347 Oesign of Venlilation Syslem of the Triple Tunnel bencath Barajas Airport using CFO and its Validation ... . ... . 363 BRE large bllilding fire tests - tire model validation for 400kW fire ... . 373 Fire Behaviour of Gypsum Plastcrboards Enhaneed with Phase Change Materiais: A CFO Stlldy .. 389 Hybrid wood/steel elements under fire ... . 407

Full-Seale CFO Simul<ltion ofGypslIm Plaslcrboard \ValI Assemblies Exposed to Fire: Effects of

Gypsum Dehydration ... . 421

Children Bchaviour during Evacuation Proeess in Sehool Bllildings

The Capability of FDS to Model Flames and Plumes Emcrging from Compartment Openings ...

441

'I

457

Development and testing of BlenderFOS, the open, community-based. useI' interface for NIST

FDS...

. ... .

471 SE1LAF: Simulaeión de Ineendios Forestales para el Entrenamiento Virtu<ll... ... . 485 Simulaeión Iluméric<l de incendios en interc<lmbiadores de transporte. Simplificacióll de condiciones de contorno y comparación de modelos LES y RANS... 507

Aplicación deI modelndo informático ai estudio de las condiciones de trabajo de los equipos de cmergcncia durante los incendios en túncles de carretem eon diferentes tipos de p<lvimenlo ... 533 Residcntial Buildings Fire Safety Application for iPhone / iPad Deviees ... . 563

POSTER SESSION

Simlllation analysis of firc-fighting strategies for subwuy tunnc! fircs: a comparison bet\\:een

natural and forced vcntilation for evncuntion stnirs protcction... 573

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Preface

Thc Inlcmational Congrcss "FIRE COMPUTER MODELlNG", 00 which this book is bascd, took

pince a1 Univcrsity Df Cantnbria, Santandcr, Canlubria, Spain on Octobcr 19, 2012. The gaul

01'

lhe Intcmational Congrcss is lo bring togcther experimental and numcrical practitioners. and fostcr discussion and cxchangc ofknowlcdgc.

Thcrc \vere 35 Papcrs sclcctcd for lhe Intcmutional Congrcss and rcprcscnting diffcrcllt counlrics (USA, UK, Canada, Jupao, Swcdcn, France, Finlund, Gcmmny, Russia, Slovukia, Italy, Greece. Portugal, Spuin, etc.). The Invitcd Lccturc abou\ "NUMERICAL SOOT MODELLING IN TURBULENT JET FLAMES ANO rOOl FIRES" was givcn by Prol: Dr. Michae1 Dclichatsios, Univcrsity ofUIsler (UK).

Wc cxprcss u specinl rccognilion for lhe work developcd in the selection of the papcrs to the Scientifie Committee of the Intemational Congress, integratcd by the out-stnnding Professors and Rcsearches, Dr. Orlando Abreu (OIDAI, Univ. ofCantabria. ESP). Dr. Daniel Alvcar(OIDAI, Univ. ofCantabria, ESP). Dr. Vytcnis 8abrauskas (Fire Sciencc and Tcchn .• USA). DL Jorge A. Capote (GIDAI. Univ. of Canlabria. ESP), Dr. Wan-Ki Chow (Hong Kong Polytechnic Uni v., China). Dr. Pedro J. M. Coelho (Instit. Sup. Técnico de Lisboa, PRT), Dr. Michael Delichatsios (Uni\". af UlsLer, UK), Dr. Nick Dembsey (Worcester Polytcchnic Institute. USA). Dr. Bogdan Dlugogorski (Univ.

01'

Nc\Vcastle, AUS), DL Scrgey Dorofec\" (FM Global. USA). Dr. Dougal.Drysdale (Univ.

01'

Edimburgh. UK). Dr. Carlos Femandez-Pello (Univ. ofCalifomia. Berkeley. USA), Dr. Charlcs M. Fleischmann (Univ.

01'

Canterbury. NZL). Dr. Pedro L. Garcia (UNED. ESP), Dr. Stcvc Gwynne (Hughes Associates. UK), Dr. Gcorge V. Hadjisophocleous (Univ. of Carleton, CAN). Dr. Yllji Hascmi (Wascda Univ., JPN), Mr. Morgnn J. Hllrley (SFPE. USA), Dr. Mare L. Jansscns (Sollth\Vest Researeh Institute. USA), Df. Francisco J. Jimenez (Univ. af Córdoba, ESP), Dr. Orunde Jom<l<lS (Tcchnical Univ. of Denmark, DK). Dr. Timo Korhonen (VTT. FI), Dr. Chris Lautenbergcr (Reax Engineering, USA). Dr. Mariano Lazaro (GIDAI, Univ. of Cantabria, ESP), Dr. Oregory T. Linteris (NIST, USA). Dr. Amablc Liiian (Polyteehnie Univ.

01'

Madrid, ESP), Df. Richard E. Lyon (FAA, USA). Dr. Andre M<lrshall (Univ.

01'

Maryland, USA), Dr. Julio M. Marli (Teehnieal Univ. of Catalonia, ESP), Dr. William E: MeU (U.S. Forest Serviee, USA), Dr. Bart Merei (Ghcnt Univ., BE), Dr. Frederiek W. Mo\Vrer (Uni\'. ofMaryland. USA), Df. Eugenio Onate (Tedm. Uni\'. ofCalalonia. ESP). Dr. Richard D. Pcacoek (NIST. USA). Df. Paulo Piloto (Instituto Politécnico de Bragnnça. PRT), Dr. David Purscr (Hartford Enviromnental Researeh, UK), Dr. James G. Quintiere (Univ. of Maryland, USA), Dr. GuiUenno Rein (Imperial Collcge, UK), Dr. Slanislav I. Slaliarov (Uni\'. of Maryland, USA), Dr. Takeyoshi Tanaka (Kyoto Univ., JPN), Dr. José L. Torero (Univ. af Edinburgh, UK). Dr. Amaud Trouve (Univ. of Maryland, USA). Dr. Patrick Van Hces (Lund Univ .. SWE), Dr. Vittorio Verda (Politecnico di Torino, ITA), Dr. Domingos

X.

Viegas (Univ. of Coimbra. PRT), Df. Sergey Vyazovkin (Univ. af Alabama. USA) and Dr. Jennifer Wcn (Kingslon Univ., UK), \\'hosc seicntisl. eontributian hus allowcd to reach a Intemational Congress with lhe highcsI quality.

Wc \Vant to cxprcss our gratitudc to lhe authors and speakers \Vho have dcdicutcd their time and effarl lo bring us in their prescntations, expcriences, methodologies and seientist - Icchnical advanccs in lhe Fire Compute r Modeling.

Prol: Jorge A. Capote Congrcss Clmirman

GIDAI- Firc Safety - Research and Tcehnology Universidad de Cantabria

iii

Santandcr, Spain Octobcr. 2012

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Temperature Analysis and Validation of Partially Encased

Beams Submitted

to

Elevated Temperature

Pif%, P. A G. '; Ramos Gavilân, A. B. 2; Mesquita, L M. R. '; Gonçalves, C.'

I Department af Applied Mechanics. Po/ytechnic Institule af Bragança. Campus Santa Apolónia, 5301-857.

Bragança. Portugal.

2 Departmenl af Mechanics. Universi/y of Sa/amanca. Campus Vin'alo • Avda. Cardenal Cisneros, 34, 49022. Zamora. Spain.

ABSTRACT

Tcmpcrature 3SSCSSmcnt af Purtially Encased Beams (PEB) was performed based on the frame work af the experimental bcnding

tcslS

ai elevated tcmpcraturcs. The heating rale af these compositc elements was 800

uC/h

in lhe first si age, rollowed by a stcady slage. This sccond stage was dcfincd to susta in temperature levei whilc increasing mechanical land. The main objective was to calculale lhe bending rcsislal1ce of PEB aI differcllt temperature leveis (200. 400 and 600 "C).

This paper present lhe experimental resuh af 12 lcsls of a more general study af 27 ICSIS,

considering lhe abjeetivc addrcsscd to analyse and validatc lhe numerical model to predicI lemperature rise of bOlh materiais (concrete and steel), in particular the time required lo heal lhe heams with almost constant temperature. This validation is fundamental for lhe general proposal of sim'ple calculation methods.

Good agreement was achieved between experimental and numericul results, obtained by

nonlinear thermal transient analysis.

1 INTRODUCTION

Partially Encased Beal11s (PEB) achieve higher fire resislanee when comparcd to bare sleel bcaiTIs. The inerease in fire resistance is due 10 lhe encased material, rcducing lhe exposed

sleel surface arca, introducing cancrete which has a low thermal conductivity. I-ligher fire

resistance can also be achieved by incrcasing lhe amounl of reinforccmcnt lO compensale for

lhe reduction of steel strength in case oI' fire, as reported by several researchers.

According to EN 1994-1-2 [1], memher analysis undcr fire conditions may be verificd using eilhcr tabulated data, simplified or advanced calculation models.

Tabulaled data rcfcrs only to composite beams ralher than PES, dcpending on load levei, and

is only valid for slandard fire exposurc and simple supporting conditions. A simple

calculation model may be used to determine fire resistance of PEB without shear connection lo lhe conerele slab. The mies for composite bcams may be applied to PEB. assuming no mec1mnical rcsistnnce ofthc reinforced concrele slab, and cst<lhlishing reduced effectivc areas of the cross seclion, [I}. This rnodel depends on Ihc lcmpernture field ovcr lhe cross seclion_

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236

INTERNA TlONAL CONGRESS

FIRE CO/l./PUTER MODELlNG

Ao advaoced ca1culation modeJ is also suitablc to analyse any lype af cross-scction in general

and partially encased sections in particular. This rncthodology \Vas used to predict lhe

tcmperature field in both materiais, \Vhen submitted to e1evated temperature.

PEB have bccn widely tested at room temperature, but only a small !lumber

01'

tests are

reported under fire ar elevated temperature. The most relevant tcsts \Vere developed by

Kindmann et ai [2], proving the importance of lhe reinforced concrete between flanges for

bending resistance. Lindncr and Budassis in 2000 [3] developed a new design proposal for

laleraltorsional buckling a1 room temperature. Maquoi et ai [4], improved the knawledge 00 the claslic criticai mament and al1 the lateral torsional buckling resislant mamen!. Makamura

ct aI. [5], lested some partially cncased girders wirh longitudinal and transversal rebars (W

and NW) to flanges, concluding 'lhat bcnding slrenglh

01'

lhe PEB was almosl !wo times

higher llmn convcntional bare stecl girders and specimens with rebar not welded to flanges

presented a decrcase of

15

% for maximum load bearing when comparcd to the welded rebar

(W) specimens. Piloto e1 ai [6] corroborale lhe conclusion about the bending resistance aI

room temperaturc af PEB und bare stcel beam, but \Vere ullable to deteel differences betwccn

the PEB load bearing, using slirnlps weldcd (W) and not welded (NW) to lhe web of the

profile aI elevated temperaturc.

This papcr intends lo analyse and validate lhe thennal bchaviour of PEB submittcd to elevalcd temperature under four poinl bending test, charactcrizing the temperature Ficld before loadillg.

This analysis was importan! lo validatc lhe bending tests.

2 PARTIALL

Y

ENCASED BEAMS

PEB were construcled by filling lhe space betwcen lhe flanges

01'

an IPE I 00 steel profile with

reinforced concrete (RC). Figure I represenls lhe nominal dimcnsions of lhe composite cross scclion.

:;;1

®

i---""--J

(11)

TEMPER.-ITURE ANALI'SIS ANO '~·/L1DATION OF PARTlALLI' ENCASED BE..JMS SUBMITTED TO ELEVATED TEMPER..·/TURE

Pil%~~. P. A. G.: Ramos Gal'ilâl1, A.

n.:

Ales/l/li/a, L. AI. R.; GOl/l"ull'!!s. C. 237

PEB

were

made of

(P

E

IOO

w

ilh

s

l

ecl

S275

JR

, u

sing

C10

encased

co

n

c

rcle

w

ilh

s

ilic

eo

u

s

aggregmes.

Four

longitudina

l

s

lc

e

l

8

500 r

eba

r

were u

se

d

wil

h

diamel

er

of 8

mm

.

Slirrup

s

\Vere dcsigned

with B

500 rebar wilh

a

di

:l

met

e

r

01' 6

mm

,

s

paced

every

167

mm. Stirrup

s

were

also partinlly welded

10

lh

e

longitudin

a

l

s

t

e

el reinforccm

c

nt

,

a

s

represenl

c

d in figure

1. PEB

we

r

e

ca

s

led in lhe

lab

oratory.

w

ilh

o

ul lhe

n

eed of fonnwork. Spec

im

e

n

s

were

t

es

t

e

d

after more

than

60 day

s,

w

ith re

s

p

ec

I l

o

lhe first

cast

ing pha

s

e

,

to

e

n

s

ure noonal

bond

adhe

s

i

o

n

.

The second

casling

phase

was

perfonned

ane week

after lhe fir

s

l. This

lim

e delay

did nol influence

lh

e

b

e

haviour of PEB

,

becausc

lh

e seco

nd

casting

u

sed

lh

e

sume concr

e

l

e

composilion

and lhe

s

ame

envi

ronrnent

a

l

cond

i

tians.

80th

casling

ph

ases

had suffic

i

cnt

c

ur

e

tim

e

and

co

ncrele pre

se

nt

e

d the

s

am

e

r

es

i

s

tance

in

bOLh

s

lage

s.

Thc

s

urfac

es

of m

a

t

e

riai

s

had no

spe

cial treatmcnl

and

were u

s

cd

as del

i

ve

r

cd

by

manul

bclurcrs

.

Sleel

e

lemcnts were

cu!"

from

long

s

le

e

! bars

,

usin

g

I

rnditio

nal maehin

ery.

Sl

i

rrup

s

\Ve

re welded t

o

lhe web ofsteel proti

l

e (W).

2 EXPERIMENTAL TESTS

Twclve

spec

imcns

\Vere

se

!

cc

ted

to

va

lid

a

l

c

lemperatur

c

011

P

E

B. Tcst

s

\Vere

grou

ped in

four

se

ri

es

lo

co

mpare tcmp

e

r

at

ure evoluli

on.

Series

I

and 3

\Vere

prepared

ror lhe

samc

tcmpera

lur

e

le

ve

i

(

400 "C)

u

s

ing diff

c

r

cn

t PEB leng

t

h

s (

Lt

=

2.5 m

and

Lt

=4.

0 m). Thc

o

lh

er

s

eri

es \Ve

r

e

pr

e

par

ed

to b

e

te

s

lcd

at

2

00 a

nd

600°C.

see

lab

l

e

I

.

Each

s

pecim

e

n

wa

s

idemified

with

:l

reference

numb

c

r

,

Icmperature levei, tota

l

len

g

th

(Lt),

l

e

ng

t

h

bctwccn

su

pporl

s

(Ls),

l

e

ngth

belween

load

(LI) and

length

exposcd

lo elevatcd

tcmperatu

re

(Lt).

Series Specimen U[mj Ls[mj LI [mj U[mj Temperature levei {0C]

8/2.4-01 8/2.4-02 2.5 2.4 1.5 1.3 400 8/2.4-03 8/2.4-04 2 8/2.4-05 2.5 2.4 1.5 1.3 200 8/2.4-06 8/3.9-01 3 8/3.9-02 4.0 3.9 3.0 2.8 400 8/3.9-03 8/3.9-04 4 8/3.9-05 4.0 3.9 3.0 2.8 600 8/3.9-06

Tuh/e J. Li.fl (~r/I!.f/ed partia/(r cllm.H·d hcam.\· (Ipl!dl/WIIS wilh lI"I'lded stirl1lps).

Specimcn

s

\Vere

te

sted using

a rcaclion porta

l

frame,

see

figure

2 .

Two hcaling stages \V

e

re

d

efined for

PEB.

The first transient

st:lge

was

u

sed

l

o

in

c

rca

se

Lemp

ew

ture le

v

ei

,

under

co

n

s

tam

h

ea

Ling

rale

.

A scco

nd

s

l

age

\Vas

define to

kept tempera

lure

a

s

unifonn a

s

po

ss

ibl

e

(12)

238

INTERNATIONAL CONGRESS

FIRE COMPUTER MODELlNG

Five different cross sections were defined to cvaluate temperature over cach PEB beam length

(SI, SIA, S2, S3A and S3).

)

rn

_~

,~,

E;J

In,,] X

.I.

.1

·3

-

.

-

. . .

@

)

é

_é

_éé

'"

~

L

,

_,

_..

.

,

_JJ

~

,

.

,

"

)

rn

~

:;

Fig. 2. 7i!Slillg colldilio/lS alld moill cross secliol/S.

Tests dcveloped at elcvatcd tcmperature used HTC device

to

increase and susta

in

temperature

during

loading,

see

figure 3. This device used electro-ceramic

resistanccs

applied

011

the top

alld on the bottom of each specimen. according to figure 4.

Fig. 3. fIca/il/g Thermal Cellln' (fITe) dCI'icc. Fig. 4. Eleclm-ceramü· rC.l'Ísfal/ce.\·.

A heating rate of800 °C/hour was applied, which lead to the first stage pcriod

af 15, 30 and

45 minutes, for 200, 400 and 600°C tcsts

,

respectively. An insulation ceramic mat was

applied to increase healing

efficicncy

and to promote uniform temperature distribution. Free

thermal

elongation

was allowed befbrc adjusting both

supports.

Supports \\lere adjusted and

load

\\Ias applied after temperature stabilization

(

60,

90 and 120 minutes,

after

the

start of

heating).

2.1 Instrumentation

Thermocouples type K were distributed inside cross section and along the length of each

specirnen, according to figure 5 and 6. Thermocouples were spot welded to steel for

rneasuring tcrnperature in steel. Small steel washers were uscd to measure the ternperature af

concrete,

wrapping them in positions

(Si

-I

C

and Si-OC) during the casting phasc.

(13)

TEAlPERATURE ANALrSIS AND VALlDATlON OF PARTlALL)' ENC/SED BEAMS SUBMln"ED TO ELEVATED TEMPERATURE

Pil%, p, A, G,; Rumo,l' GlII'i1dll, A, B.; Ak.l"q/liw, L. M. R.; GOllçah'l'.\·, C.

/ -

....

.

SMi ~:~:: ~.l (:: '~':'I--SIAJS::!lS3/S3A.QSI

S2IS3·RS --'

i

:::'

\

,

~

-,

-

_):-

'

::-1·

1 '

~

J

j

-

;

1,.: S2ISl.,C " .'. j:_'.; 1'-S:!IS]·OC S!I$3.WS..A'J ('"):'\; 1 -

-

,-

-

->:

':1" :" tr-5Mi SlA/S!lS3A.QSh~:":":':' t ..: ... __ ., - -''Io? IIY"

Fig. 5. Thi'r/llflcouplL' prHilirm.l"/iJr allllltlill .\·L'ClirJll.\·. Fig. 6. TIIl'/"JlloL"ouple/iw positioll Si·lC.

239

Th

e

nn

oco

upl

es we

r

e

a

l

so

u

se

d l

o co

n

tro

l lh

e

el

cc

lri

ca

l h

e

atin

g p

r

ocess (

S

M

i

).

Th

csc

thermoco

u

p

l

es \V

e

re di

r

ect

l

y co

n

ncc

t

ed to lhe co

n

tra

i

uni

t

o

f th

e

H

eating T

h

c

rma

l

Centre

dcvi

ce (

7

0 kVA maxim

u

m p

o

wer).

T

h

e Hc

uting Th

e

rm

u

l

Ce

ntre wa

s

abl

e

l

O

d

e

liv

e

r h

ea

l

by

Jo

ul

e

cffec

l

, us

in

g

spec

i

a

l

c

l

ect

ro-

ceTilmic resis

t

a

n

ces. Tc

m

pe

ralur

e was con

t

ro

ll

ed

i

n rea

l

ti

me by

lh

e

c

ont

ro

l uni

t,

m

easu

rin

g

t

c

m

pera

lur

e

in t

\Vo a

n

d fou

r

po

in

ts.

f

o

r m

e

diuTll

(

s

e

ri

cs

J

a

nd

2) a

nd Inr

gc

t

es

l

se

ri

es (se

r

ies 3 nnd 4)

r

es

p

ec

ti

ve

l

y.

Fi

g

ur

es 7 a

nd 8 r

e

pr

ese

nt lh

e

r

es

ult o

f

in

frme

d thermo

g

ra

p

ll

y a

nalysis f

o

r lh

e

ultimat

e

b

c

ndi

ng

li

mit

state

ai t

he

e

lld

of tests

8 /

2.4-04 il

n

d

8 /

3.9 -

05 ,

rcspec

t

ive

l

y.

B

ot

h

fig

ur

es

d

e

m

o

n

strn

t

c

th

c

h

eal

flu

x a

t th

e bea

111 ex

tr

e

mi

ty a

nd

l

h

e

ffi

c

i

c

n

cy o

r lh

e

in

s

ulari

o

n

.

T

h

e

h

eat

i

ng

pro

cess wns co

ntr

o

llcd l

a de

t

e

nni

nc

thcnll

a

l

s

t

ea

d

y

co

n

d

iti

o

n

s

(second

s

t

agc),

b

e

f

ore

l

oa

din

g.

T

e

m

pCrJlure d

i

s

tribuli

on a

l

o

n

g eac

h P

E

B

was a

l

so

m

o

nil

o

r

cd

.

u

si

n

g

di

sc

r

e

l

e

tcmp

cra

lur

e

r

ca

din

gs by the

rm

oc

oup

les and also

fi

e

l

d rcad

in

gs by

in

rTU

r

ed thcr

m

og

ra

p

h

y.

2.2 Temperature measurements

T

e

mp

CrJ

lUr

e was reg

i

s

l

crc

d in b

o

th

s

t

ages (

t

ru

n

sic

nt

-

firs

l

s

l

agc a

nd

s

t

ea

d

y

-

s

c

co

n

d

s

l

age).

(14)

240

INTERNA TlONAL CONGRESS

riRE COIIIPUTER MODELING

Thesc results were plotted for

section

S2. Temperalure evolution in steel follows the trend of

the heating rate, while temperature ofconcrete prcsents the traditional

effect ofhumidity (near

100°C), followed by lhe

s

ame heating rate. Temperature is almost unifonn in the cross

section during the steady state

(constant

temperature levei).

Figures

10 ,

12, 14 and 16 collect the temperalure data fram output stecl

(Si-OS)

in each

specimen

of each series

,

over the PEB length

,

for thrcc specific time instants (beginning.

intennediate and

steady stage).

Temperature di

s

lribulion along each PEB is not canstant

beca u

s

e the heat flaws by

conduction

to the beam extremities, the length of th

e

b

e

am exposed

to elevated temperature

(LO

is 52 '

%

and

70%

with respect to the total length of lhe beam

(Lt),

for the mediuITI and large

series

re

s

pectively and finaIly lhe insulatian near the beam

extremities was nol efficient.

lrnlJ"f>'llr< I"C] '"r--c~---~---C--1 ~. ...

....

_.-.:::-:..~.-:.-.;-.;, _ ... ~._.

...

'

-: .

..

.

,...

!-:

~

.. '

'i

r.

"

V

,

,,

,

,~

,,

,,,~,,

,

7,,,,;;:;-,

q

:

... "". ' I w.!_~.Q: (\~.fI5I1 : ./ ,/{'::'. "-... llt: _I·a: ,5:·0Cl :

~

,

~

.:.'

-

··~

I

U'

.!.

t

-lJ.!

l!;'

;'

.

\\

'51

1 i

.' :. !I>;!H : 1;'·1l1 : :

r

Ut;1HI!{l;'~1 :

-

I_ I

-

.I :<1

-Fig. 9. Healillgfiw le.\·1 B/2.4-02, seclio}/ 52.

Tr",""'_I'e] ,~

,

.

,~

•

,"

•

Fig. 11. Healingfor lesl B/2.4-05 .. \-eclicm 52. 1""1"'""""'" ]"CI ; -IOO'C --'-~~--:-':-:':;;'-:'.=:i.~ .:

/;':

.

~·

~

{

I

I'

U.Q1~~:"'.{)5lo1

.l

i

.

' ,~ , "

~

n'l'.(I'I~-::OÇJ . 'I!)'I-Q'I<;:~~" .... ,'" " ' . !!I'l~-II.:'1:WI)I: . ·~.!l?'"!1:(<;:·~.:1

-f nIJ.9-Q:IS::.1!S1 '1. ••• ' ) ...

:

·01 • _ _

-I- l-I

Fig, 13. HeotillgjiJr lest B13. 9-02, SL'cliOIl 52.

.'I:"t.

Fig. lO. Temp. dislri. 01/(1 ~\'ol/llio}/fiJ/' te.I't sedes I.

IfWI""''''''rcJ

,.

,

.

,

.

•

•• x.,~

..

Fig. 12. Temp. (1i.~/ri. {//ul t!mlutiollfiJl' tesl.l't'ries 2,

~

'

~"~

"

~

';;;;;;;;~;;;;;;

~~;-

---~

~

,~

• ' x.,1 .• 16

..

(15)

TEMPERA TURE ANAL}'SIS AND VALlDAT/ON DF PARTlALLY ENCASED 8EAMS

SUBMIITED TO ELEVATED TEMPERATURE

Piloto. P. A. G.; Ra/llos Gm'iltÍlI. A. 8.; Mesquita. L. M R.; Gemça/n!s, C.

--.-:.-=.": .-. :-'-=-.'

..

.

..

.

-::

.

-

.

'

..-

-.' (iIJ,..,{!>;"-OQ.11 , nJMj(~:·n\ .. , 241 :\11,

Fig. 15. Hl!lIfillgjiJr te.~f o/3.9-t)5, sectio" S2. Fig. /6. ft!llIp. disfri. uml l!1'O!l/fiel/ljór ti!st .~el'ks -I.

3 NUMERICAL MODEL

Thc numerical model used Iwo dimensional linear linite clcments (Plane 55) from Ansys,

with transienl and nonlinear malerial bchaviour, [7]. The element used four nodes wilh one

degree offreedom (temperature at each nade) and linear inlerpolnting funclions.

The modcl was refined lo allow for lhe best cOllvergencc soJulion bctween experimental and

numerical results. Figure 17 represents lhe finilc e1emcnt mesh, used to simulate

reinforcemclll, concrete and stccl. The mesh presents 3430 finitc clcmenls and 3514 nades.

The boundary canditions were defincd in lhe IOp and in the bailam of lhe profile, following

lhe experimental healing curves (prescribed lemperahlre). Thc initial condition was 3iso

sclected from experimcnls, taking into to considcration the starting tempcmture in lhe cross

scction.

Three Célses were selected to represent lhe behaviour of PE8 at diffcrent lempcrahlre Icveis.

The specirncll lests 8/2.4-06, 8/3,9-03 tlnd 8/3.9-05 \Vere seleclcd to compare the lemperaturc

rcsults for 200, 400 and 600

u

C

,

respcctively,

'. '.

:

'

p

,',::

'

1 <

(16)

242

INTERNATIONAL.. CONGRESS

F1RE COMPUTER MODELlNG

Perfect cantuct \Vus assumed between both materiais.

Thrcc dimensional thermo-mechanical madel

is

under development to validate fuH

cxpcriments,

3.1 Material properties

The material properties \Vere defined according to Eurocodes, for both ,materiais [8.9]. The

tcmperature dependence of thennal conductivity.

specific

heat and specific mass

is

represented in the next figures

(17

-2

2).

10.1111""1 .~

••

;110.' 100' oro •

•

~

o

.

O~

Fig. /7, CO//(I/lclil'i~I'fi!l' sleel.

('rOl:"1

-

---

0 -

J \

~ ~ O~ ~ 0- O~ 1("'1

Fig. /9, Specijic hClIt/iJr,\'tee!.

·"'

1 ---1

-lrq

Fig. 2/, Spec(jic massjár stec!.

o •

Fig. 18, COlldllctil'ity/úr cOllcrelc,

Cp 1J.l~"1 ~

-,.~

A

,-.

_J

~ ~, ~

,.

••

,~, ,~ I ('r[

Fig. :!O, Specijic 1II!I11for collcrele (3% hllmidi~I').

,>110.::"'1 :'JO

r---,

~

I

~o

I

-

.

---~ ~

o

.

~ TI'!')

Fig. :!2, Spccijic mas,l'jiJr Cal/crere,

,~

(17)

TEMPERATURE ANAL)'SIS AND VALlDATION OF P..IRTlALLJ' ENCASED /JEAMS

SUBMIITED TO ELEVATED TEMPERA TURE

Piloto, P. A. C.; Ramo.\" Cc",i/ulI, A. B.: Mes/[Ilita, L M. R.; COllçal\"l!s. C. 243

3,2

Temperature

results

and comparison

The lemperature

results \Vere

dctcrmined

ror every

nodc

af

lhe

cross

sect

ion,

buI

lhe time

hi

s

tory

ror each node lacat

i

on was defincd according

to

the position af each

th

ennocoup

l

c

u

s

ed

ror

compari

s

on. F

i

g

ures

23-28 prcsent l

h

e comparison between l

h

e

tempcratur

e

evo

luti

on

in bOlh mal

c

rials

(slee

l

and cancrelc) for tc

s

l

s

aI 200

,

400 and 600°C.

Th

e

r

es

ult

s

how good agrcement

between lhe

experimenta

l

resuhs

and lhe Ilum

er

ical

res

ult

s

.

Maximum

l

e

mperature

differcncc

bctwcen

experimenta

l

mcusurements and nurncricul results is also

ident

ified

for

cach materia

l.

1,_ ",.,,['q ~.

'"

t----/;

~..:::;~<~

,

1:tI

1 3II"C

t

.

_.<

..

U\:-oo.·

/ :-_01,\:·,,)) J :--....I!\:Ul , 1\: 14,,>:·0\11 II~ '·"'I~:.fN>, I .I~

...

" :I· . . '\..:·1l'o1 >l'" ,.-11.

..

~ .'

"

1 '/

Ú:"I"""\:'''M .~-==~'"O'C'="=·C""OC

_

:= __

~:--'

,o. :I11III xo.o .\001 :OolO

11-1'1

Fig.

n

.

TClIIl'emllll'e el'ollltiollji,w stcel. /J/J..I-()(j.

l".,. ... rq

l

\l ....

.'

..

\

,

-Fig. 25. Tell/fleralllj"e em/lll;o/lfor .\"fed. B/3.9-03.

1_''''''''''l"n

11"'1_1

Fig. 27. Tempera/li!"!! 1!1'0/1I1hm/m .I·/ed. B/3.9-05.

Fig. 14. T!!/IIpe/'Owre L'm//lliol1.1iwcO/lcl"I!Il'. 8/2.-I-()6.

'"

~ ~.;r-.~---~ -fio" ,j; I/~ -~ :00 ~r?í '--'1\:.QC1 >lU ... 11-1'11 ; / / ~"""""",~,K'1 111'1 ~...- 11 , .... J(\:·OC.

-11-:

~==

11111O::tuII)tM

-

=~I

=:

:--

,,'

,,~

'

~=l~,~_:_i~

_ _ _

-

_'=;;==~

:-_~

1IIOot

1" '1_[

Fig. 26. T!!/JIpe/'flt/w" (!m/ll/ifm/ór ("1111("/'<'/1', B/3.9-03.

I .. ·~<t"·"rq ~

..

I

-

I

/./d

_

;'

''''''

''-

?Cr

-

1

-7

•

• (-,

,,f'

:-_,..,W':.II(') ,.I --.... .. ,\: ... , //' IlJ . . ,I\:.oo

..

_..

/ .' ~- M ... n.rrM ...

-~~

~/~~==

ll l l l O = - : w . ; o JI I O I I ' U I l O _ l I I O l . M O

.~

,

.

11"'1.1

(18)

244

INTERNATIQNAL CONGRESS

FlRE COMPUTER MODELlNG

The numerical simulations validated the time rCCJllired to achieve lbe steady state condilion

and were able to predict temperature evolution in both materiais (stecl and concrete). Small

differences between numcrical results and experimental measuremenls were dctccted and may

be explained by the boundary condilions. The numcrical model also used perfcct insulation

while experiments presented some residual

hem

loss across lhe ceramic fibre insulation

material. Perfcct contact was also considered betwecn steel and concrete, which can modify

the hei:H flow and adhesion betwcen both materiais and finally, lhe muteriô31 properlies \Vere

nol measured and \Vere assllmed from references.

4 CONCLUSIONS

Thennal mmlysis of twelve experimental tests was presented, rcgarding two heating slages of

PEB submitted lo elevô3ted temperatures (200,400 and 600°C). Temperaturc was measured in five different sections which allowed analysing the heating themml effeel along the lenglh of

eaeh specimen.

Nonlinear transient finite elemen! analysis was used to validate the temperature dislribution

over lhe cross seclion S2 and also used to predicl lhe required time to estublish lhe thermal

steady condition, previously slagc to apply the mechanical 10ô3d. Good agrcement was

detennined between experimental and numerical resulls.

ACKNOWLEDGMENTS

The authors gratefully acknowledge lhe material suppOrl of the following companics: Arcelor

- Mittal (Spô3in),

J.

Soares Correia (Portugal), Fepronor (Portugal) nnd Hierros Furquel

(Spain).

REFERENCES

J.

CEN - EN 1994-1-2; "Eurocodc 4: Design ofcomposite steel and concrete structures -Pari

1-2:

General rules - Structuml tire design"; Brussels, August 2005.

2.

R.

Kindmann,

R.

Bergmann,

L-G.

Cô3jot,

J.

B. Scleich; "Effect of reinforced concrete

betwccn the flanges of

lhe

stecl profile

of

partially cncased compositc beam";

Joumal

of

CO

IlSlru

cl

ional

S/ccl

R

cscarch,

27. pp 107-122, 1993.

3.

Joachim Lindncr, Nikos Budassis; "Lateral torsional buckling of partially encased compositc beams without concrete slab";

Composi

l

c C0I1Str/lCli0I1

il1

steel

al1d

COllcrele

IV,

cO

l1ferel1ce pro

ceedil1gs,

Mô3y 28th to June 2nd, Banfr, Alberta, Canada. 2000.

4. R.

Maquoi, C. Heck, V. Ville de Goyet,

et

aI,

(European cOOlmission), "Lateral torsional

buckling in steel ô3nd composite beams"; ISBN 92-894-6414-3; Book 1,2 and 3;

Tecllllical

(19)

TEMPERATURE ..INALJ'SfS AND I:·ILlDATION OF PARTIALLI' ENCASED BEAMS

SUBMJ1TED TO ELErATED TEMPERATURE

Piloto, P. A. G.: Ra/JIoJ Gal'i/â/J, A. B.: Mesquita. L. M. R.: GOIIÇlllw!.\·, C. 245

5. S.

Nakamura,

N. Narita

,

"Bending

and

shear

st

rengths

of partially encascd

composite

1-girders"

,

JOII/'l1al

(?f"Col1st

rucliol1al

S/cel R

e,

\

'e

ar

c

h, 59, pp.1435-1453

,

2003.

6. Paulo A. G. Pil

o

to

,

Ana

B. R. Gavilán

,

Lu

is

M. R. Mesquita

and Car

l

os

Gonçalves

;

"High

tempernture

t

es

t

s

o

n

partially cllcased beams

";

proceediugs 0/

lhe

7 th

JlIlematioual

COI!ferel1ce 011 Struclllres in Fire,

pp: 285-293, Zurich

,

Swit

ze

rland

,

6-8

June

201

2 eds.:

M. Fontana,

A. Frangi

,

M. Knobloch

.

Eidgenõssischc Techni

sc

he

I

-

Iochschule Zürich and

EMPA Malerial

s

Seienee

&

Teehnology

(

2012).

7. ANSYS,

Inc

,

Rclcusc

14.0,

"Help Syslem, M

ec/

ulI1ical APDL Th

eo

ry

Re/crel1ce

",2012.

8. CEN; EN

19

93 -1-2;

Eurocode 3, Design af stccl structures - Part

1-2:

General

rulcs

-StrucLural fire dcsign.

April

2005.

9. CEN;

EN

19

92 -1-2

,

"

Eurocode

2: Dcsign

ofco

ncr

ete st

ructure

s

-

Pari 1-2

:

General rule

s

Temperature analysis and validation of partially encased beams submitted to elevated temperature

n.

International Congress

FIRE COMPUTER MODELlNG

UNIVERSIDAD DE CANTABRIA

y

Inlernalional Congress

FIRE COMPUTER

MODELlNG

por

Contents

97

259

'I

FDS...

. ... .

Preface

01'

01'

01'

01'

01'

01'

X.

Temperature Analysis and Validation of Partially Encased

Beams Submitted

to

Elevated Temperature

ABSTRACT

tcslS

uC/h

1 INTRODUCTION

01'

01'

15

2

PARTIALL

Y

ENCASED BEAMS

01'

®

i---""--J

n.:

PEB

were

made of

(P

E

IOO

w

ilh

s

l

ecl

S275

JR

, u

sing

C10

encased

co

n

c

rcle

w

ilh

s

ilic

eo

u

s

aggregmes.

Four

longitudina

l

s

lc

e

l

8