Publisher’s version / Version de l'éditeur:
Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la
première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca.
Questions? Contact the NRC Publications Archive team at
PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information.
https://publications-cnrc.canada.ca/fra/droits
L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.
ISIS International Workshop on Innovative Bridge Deck Technologies [Proceedings], pp. 1-39, 2005-04-01
READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE.
https://nrc-publications.canada.ca/eng/copyright
NRC Publications Archive Record / Notice des Archives des publications du CNRC :
https://nrc-publications.canada.ca/eng/view/object/?id=8e5c56de-715d-4372-9ec5-12d0179b3c44 https://publications-cnrc.canada.ca/fra/voir/objet/?id=8e5c56de-715d-4372-9ec5-12d0179b3c44 NRC Publications Archive
Archives des publications du CNRC
This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur.
Access and use of this website and the material on it are subject to the Terms and Conditions set forth at Integrating fire resistance into infrastructure projects
http://irc.nrc-cnrc.gc.ca
I nt e grat ing fire re sist a nc e int o infra st ruc t ure proje c t s
K o d u r , V . K . R .
N R C C - 4 7 6 5 7
A version of this document is published in / Une version de ce document se trouve dans: ISIS International Workshop on Innovative Bridge Deck Technologies, Winnipeg, MB., April 14-15, 2005, pp. 1-39
Integrating Fire Resistance into
Infrastructure Projects
V.K.R. Kodur
Outline
• Background – Fire design
• Need for Fire Resistance in Infrastructure • Fire Performance of HPM - Complexities • Fire Resistance Assessment
• Integrating Fire into Design Design Guidelines
Case Studies
Fire Safety
• Fire Safety
Fire - Severe Conditions
Buildings - Design Requirements • loss of life and property
• Fire resistance - structural systems
safe evacuation - occupants & fire personnel minimize property damage
control spread of fire
• Current Requirements - Buildings
FR Requirements for
Infrastructure
• Fire and Infrastructure
Traditionally no specific fire resistance requirements Bridges, Tunnels, Open spaces
• Growing recognition on the need for FR requirements
Recent Incidents – Fire Accidents Use of (New) HPM Materials
Deteriorating Infrastructure/Decks Severe Environment Conditions Economical Impact and Safety Strategic Considerations
Fire Incidents
• Euro Tunnel Fire - Nov 96 Burned 10 h – 1000°C Severe damage • injuries (8), services (£50M) • thermal spelling • RC tunnel rings (100's m) • av. depth 10-20 cm Strength - 80~100 MPa Permeability - low
• Major repairs – damages
Fire-Induced Spalling of HSC Tunnel Lining & Buckling of reinforcement in
Channel Tunnel due to Fire on Nov 18, 1996
Fire Resistance
-Materials
• Fire Resistance of Systems Constituent materials
Traditional materials
• concrete, steel (protected) masonry • good FR properties
HPM
• FR properties - not good
High Performing Materials
• HPM - HSC, FRP, HPS Benefits • Superior performance – Strength, Durability – Corrosion resistance Applications• Bridges, Infrastructure projects • Buildings, Parking garages
– FRP- Internal & External reinforcement
» Retrofitting – columns, beams » Rebars and prestressing rods
– HSC - replacing NSC
Fire Performance - FRP
Members
• Design Considerations Smaller c/s size
Min. cover - Corrosion free • Complexities - FRP
Various types, Resin-matrix composite Lower critical Temp
Combustible
Variation of Strength with
Temperature for Different
Materials
Fire Performance - HSC
• NSC - good fire resistance
• HSC - behaviour diff. from NSC
• Spalling
Pressure build-up - pore pressure • Moisture migration
Low permeability
Strong pressure gradients Explosive spalling
Loss of C/S – fire resistance Ext. damage – structure
Early spalling - safe evacuation Cover – temp in rebar/ties
Fire Resistance
Requirements
• Columns 1-3 hours Stability, no collapse • Steel columns – applied protection – limiting temperature • RC columns– min cover to rebar – limiting temp. in rebar
Fire Resistance
Requirements
• Slabs 45 min to 2 hours Stability, Integrity • Steel decks – applied protection – limiting temperature • RC/PC slabs– min cover to rebar, min. c/s size – limiting temp. in rebar/ tendon
• Fire load • Temp. rise • Ventilation • Design features • Location
Infrastructure – Fire
Scenarios
Integrating Fire in to
Infrastructure Design
• Design Guidelines – Fire Resistance • Case Studies
Concrete Slab with FRP Internal Reinforcement HSC Columns
Concrete Slab with FRP
Internal Reinforcement
• Fire resistance evaluation of an RC Slab
Based on temperature profile
• slab characteristics • critical temperature • Failure Criterion < Tcr in rebars T on unexp side • < 140°C (Av) • < 180°C (1 pt) no flames on • unexp side
Design Guidelines
• NRC-PWGSC JRP - FRP reinforced RC Slabs Strength properties of FRP at Elevated Temp.
• critical temperature
Experimental Studies - FRP-RC slabs Numerical Studies
Design Guidelines
• CSA S806 for FRP in buildings
Numerical studies Rebar type • Steel, FRP Concrete type Slab thickness Cover thickness Time-Temp Graph • Slab charact. • Critical temp • CSA-S806 0 100 200 300 400 500 600 700 800 900 1000 0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 Time (min) T e m p erat u re at R e in fo rcem en t D e p th ( o C ) 20 mm-(Slab C1) 30 mm-(Slab C2) 50 mm-(Slab C4) 40 mm-(Slab C3)
Critical Temperature Limit for Steel (593oC)
Critical Temperature Limit for FRP (250oC)
60 mm-(Slab C5)
Effect of concrete cover thickness on FR of FRP-RC slabs
Design Chart - FRP-RC
Slabs
Critical Temperature of
FRP Rebars
Slab Characteristics t = 120 mm
tc= varying
Agg. = Carbonate Exp - ASTM E119
tc= 20 mm S = 95 m G = 30 C = 20
Design Charts - FRP-RC
Slabs
Slab Characteristics t = 180 mm
tc= varying
Agg. = Carbonate Exp - ASTM E119
tc= 40 mm S = 240 m G = 65 m C = 45 m
Design Charts - FRP-RC
Slabs
HSC Columns - Design
Guidelines
• HSC columns • Reinf. detailing tie configuration bending ties @ 135° tie spacing - closer cross tiesminimizes spalling enhances FR
Design Guidelines
• Carbonate aggregate (limestone) • Normal density aggregate
• Minimum dimensions
1h - 12” 2h-16” 3h-24”
• Concrete cover thickness
View of HSC after Fire
Test
Current Fire Research
• ISIS-NRC-Industry Research Project Fire Resistance of FRP-RC Systems
• FRP wrapped columns • FRP Strengthened beams
• FRP Strengthened beam-slab assemblies
Partners
• National Research Council • ISIS Canada
• Queen’s University • Industry Partners
Project Elements
• Experimental Studies 16 full-scale fire tests 12 small-scale fire tests • Numerical Studies
develop computer programs evaluate fire protection
• Develop design procedures • Outcome
computer models design procedures
design provisions for standards
FULL-SC A LE FIRE TESTS
Pha se 1: Fa ll 2 0 02
Te st Se tup fo r C o lum n Fire Te sts
Re stra ine d Ag a inst Ro ta tio n (b o th e nds)
Ste e l End-Pla te
FRP-Wra ppe d Re info rc e d C o nc re te C o lum n (instrum e nte d w/ the rm o c o uple s a nd stra in g a ug e s)
Lo a d Applie d fro m Be lo w
C AN/ ULC S-10 1 Sta nda rd Fire
NRC C o lum n Furna c e
A A
FRP she e t a nd va rio us fire p ro te c tio n sc he m e s to b e te ste d Pha se 2: Winte r 2 0 03 Applie d Lo a d FRP-Stre ng the ne d Re info rc e d C o nc re te Be a m
(Instrume nte d with the rmo c o uple s & strain gauge s)
A
A
Se c tio n A-A
C AN/ ULC S - 101 Sta nda rd Fire
Te st Se tup fo r Be a m -Sla b Fire Te sts
FULL-SC A LE FIRE TESTS
Pha se 1
Te st Se tup fo r C o lum n Fire Te sts
Re stra ine d Ag a inst Ro ta tio n (b o th e nds)
Ste e l End-Pla te
FRP-Wra ppe d Re info rc e d C o nc re te C o lum n (instrum e nte d w/ the rm o c o uple s a nd stra in g a ug e s)
Lo a d Applie d fro m Be lo w
C AN/ ULC S-10 1 Sta nda rd Fire
NRC C o lum n Furna c e
A A
FRP she e t a nd va rio us fire p ro te c tio n sc he m e s to b e te ste d Pha se 2 Applie d Lo a d FRP-Stre ng the ne d Re info rc e d C o nc re te Be a m
(Instrume nte d with the rmo c o uple s & strain gauge s)
A
A
Se c tio n A-A
C AN/ ULC S - 101 Sta nda rd Fire
Column 2
Immediately After Failure
Column 2
Immediately Before Testing
FRP-strengthened RC
Column : Before and After
Fire Test
Preliminary Guidelines for
FRP’s under Fire
• Unlike conventional reinforced concrete
members,FRP-strengthened structural systems require suitable fire protection to achieve fire endurance ratings under increased service loads. • The performance of protected FWRC columns at high
temperatures can be similar to, or better than, that of conventional RC columns.
• Insulation properties (thermal conductivity, specific heat and
thickness) are the key parameters to consider in the selection of insulation schemes for FRP- strengthened structural systems. • Further studies proposed in Phase II, will result in fire guidelines
Numerical Studies
• Numerical Model
predicting the behaviour of HSC column • Numerical Procedure fire temperature • ASTM curve C/S temperature • thermal properties strength • mechanical properties
Numerical procedure for
fire resistance
Fire Performance
Requirements
• Codes - UBC/NBC
Fire Resistance Ratings Flame Spread Ratings
• Smoke developed classifications
Non-Combustibility Classifications • Fire Resistance
Slab Characteristics t = 150 mm
tc= varying
Agg. = Carbonate Exp - ASTM E119 tc= mm S = m G = m C = m
Design Charts - FRP-RC
Slabs
Slab Characteristics t = 120 mm
tc= varying
Agg. = Siliceous Exp - ASTM E119 tc= mm S = m G = m C = m
Design Charts - FRP-RC
Slabs
Slab Characteristics t = 150 mm
tc= varying
Agg. = Siliceous Exp - ASTM E119 tc= mm S = m G = m C = m
Design Charts - FRP-RC
Slabs
Slab Characteristics t = 150 mm
tc= varying
Agg. = Siliceous Exp - ASTM E119 tc= mm S = m G = m C = m
Design Charts - FRP-RC
Slabs
View of HSC Columns
With and Without PP
Fibres
Summary
• By adopting design guidelines, such as the addition of fibres and an improved tie configuration, spalling in HSC members can be minimized to a significant extent and fire endurance can be enhanced.
• The polypropylene fibers are much more effective in minimising spalling in HSC under hydrocarbon fires.
• The fire endurance of HSC columns with equivalent levels of confinement is lower than that of NSC columns. However, fire endurance up to 4 hours can be obtained with HSC columns if the guidelines are adopted in design.
Complexities - FP of HSC
• NSC - good fire resistance
• HSC - behaviour diff. from NSC • Spalling
low porosity, high density pore pressure
• No guidelines for fire
ACI 318/216, CSA-A23.3, NBCC • Solution - eliminate fire protection
