Prof. Stijn MATTHYS
Workshop of the Belgian fib member group - 23 January 2020
fib REPORT ON DESIGN OF CONCRETE MEMBERS WITH FRP
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
4/50
FRP (fibre reinforced polymer)
FRP → thousands of
continuous fibres in a
polymer matrix, forming a
composite with high
strength, stiffness and
durability
+ high strength
+ low density (≤ 20% than steel)
+ excellent durability
+ high E-modulus (comparable with steel)
+ excellent fatigue characteristics
+ ease of application
- limited failure strain
- higher material cost
- specific durability issues possible (UV, alkalis)
- fire resistance
6/50
FRP reinfrocement
FRP strip & sheets
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Tensile diagram
0
500
1000
1500
2000
2500
0.0 2.0 4.0 6.0 8.0 10.0
Rek [%]
Sp
an
nin
g [
N/m
m²]CFRP
Stalen plaat
AFRP
GFRP
G: glass; C: carbon; A: aramide; B: basalt; SC: steel cord
σ (GPa)
ε
Mild steel
0.02 0.04
2
6
4
GFRP
AFRPCFRP
Steel plate
Strain
Str
ess GFRP/BFRP
CFRP/SCRP
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Typical values (fibre volume ~ 60 %)
Property CFRP GFRP AFRP Steel plate
Tensile strength [MPa] 600-3000 400-1600 600-2500 300-600
Modulus of elasticity [GPa] 80-500 30-60 30-125 200
Failure strain [%] 0.5-1.8 1.2-3.7 1.8-4.0 >10
Density [kg/m³] ~1550 ~1950 ~1400 7850
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Ciment armé[1st patent 1851]
FRP strengthening[1987]
FRP prestress[1980]
1990’s manyapplications & growing
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Reinforcing and strengthening with FRP
FRP rebars and prestressing reinforcement Externally applied reinforcement
11/50
FRP reinforcement in new structures
Niche markets
12/50
Externally applied reinforcement
Ease and flexibility of application
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
fib T5.1 ‘FRP
reinforcement for
concrete’
Part of fib
commission 5
‘Reinforcements’
Meetings twice per
year
90 members
Stijn Matthys
Maurizio Guadagnini
Task Group Chair
Deputy Chair
15/50
Work modus → supporting networks
Action TU1207
FINISHED
NEW
16/50
fib Bulletins by Task Group 5.1
17/50
fib FRP course
URL: www.frpcourse.eu
fib Workshop 12 November 2019, Naples
Presentazione del bollettino fib 90
“Externally applied FRP reinforcement for concrete structures” - Bulletin 90
fib B90 on Design of
Concrete Members
Strengthened with
Externally
Applied Reinforcement
19/50
T5.1
Technical bulletins
FRP in EC2
FRP in MC2020
Compendium
Training
Running activities
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
1. General
2. Materials, systems and techniques
3. Basis of design and structural analysis
4. Durability considerations
5. Bond
6. Ultimate limit states for predominant
static loading and fatigue
7. Serviceability limit states
8. Ultimate limit states in seismic retrofitting
9. Detailing
10. Practical execution and quality control
ISBN 978-2-88394-131-1
240p (vs 138p for fibB14)
Wider scope of techniques
NSM added in detail
Updated design formulations
25/50
Types of EAR
26/50
► increase flexural capacityincrease stiffness (less deflections)
► increase shear capacity
► strengthening of columns
Types of strengthening
Vuurmolen Overijse
27/50
Table 1. Material safety factors for FRP tensile strength.
Design situation Safety factor*
Persistent/transient 1.25
Accidental 1.00
* These safety factors imply that the quality control provisions on the FRP materials and products,
as well as their installation, are according with the provisions of Chapter 10. The safety factors
adopted in seismic retrofitting are higher, see Chapter 8.
Constitutive material models
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xlim ≤ 0.45d for concrete type C50/60 or lower
xlim ≤ 0.35d for concrete type C55/67 or greater
x the depth of the compression zone
d the effective beam depth
Warning by sufficient curvature
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unstrengthened
(Q1)
Qd1
strengthened
(Q2 > Q1)Qd2
accidental loss of FRP EBR
→ failure or not?
Q2 > Q1
Load and
material safety
factors
Reduced safety
factors (or = 1)
(EC1)
Accidental design situation
In this case, extra attention should be paid to all relevant accidental
situations and specific points for the designer are listed.
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
31/50
Upcoming (1): FRP in EC2
CEN/TC 250/SC 2/WG 1/TG 1
Strengthening and reinforcing with fibre reinforced polymers
Eurocode 2
Scope:
• Embedded FRP
reinforcement
• Strengthening of existing
concrete structures with
FRP
Note: scope is more narrow than in
fib Model Code.
Proposed annexes (after
considering Project Team 3
comments); comments national
CEN bodies to be addressed
33/50
Upcoming (2): FRP in MC2020
35/50
Upcoming (3): Design examples
NN
Design examples for reinforced concrete members reinforced or strengthened with FRP
PART I – Strengthening of concrete structures with externally applied reinforcement
# Title Main Autors Additional contributors
3 STRENGTHENING OF RC MEMBERS
31 Flexural strengthening by EBR
311 One-way slab Gent (Arslan, Stijn) Thanasis T., Christoph C.
312 Two-way slab Timisoara (Florut) Gabriel S.
313 RC beam Milano (Tommaso) Thanasis T., Stijn M.
314 One-way slab with prestressed EBR Lodz (Renata) Christoph C., José S-C
315 Statically undetermined RC beam abt (Mark V.) Stijn M., Eva O.
32 Flexural strengthening by NSM
321 One-way slab Minho (Joaquim, José) Renata K.
322 RC beam Milano (Tommaso) Joaquim, Renata K., Sandor S.
323 RC beam with prestressed NSM Lodz (Renata)
33 Shear strengthening
331 EBR shear strengthening Milano (Tommaso)
332 EBR shear strengthening continuous girder UPC (Eva), USFD (David E.)
332 NSM shear strengthening Minho (Joaquim, José) Renata K.
34 Confinement of columns
341 EBR confinement of axially loaded columns DUTH (Theodoros) Kocaeli (Erkan E.)
Confinement with EBR Milano (Tommaso)
342 EBR strengthening in combined bending DUTH (Theodoros)
343 EBR confinement of slender columns Gian Piero Lignola (Napoli)
4 STRENGTHENING OF PC MEMBERS
410 Flexural strengthened with prestressed EBR/NSM Lodz (Renata) Christoph C.
420 Shear strengthening UPC (Eva), Lodz (Renata) Arslan
5 SEISMIC RETROFITTING
51 Column: lateral drift – lap splice – shear DUTH (Theodoros) Ciro, Erkan E., Thanasis T.
52 In plane shear of RC walls Timisoara (Florut)
53 Beam-column joint Naples (Ciro, Andrea) Thanasis T.
541 Strengthening of RC frame (FRP combined with steel bracing)Naples (Ciro & co)
542 Seismic strengthening - whole building = 54 Nothingham (Georgia T.), Thrace (Souzana T.)
6 ACCIDENTAL SITUATIONS/SPECIAL CASES
61 Fire design of strengthened RC member UGent (Alessandro,Stijn) Luke B.
62 Strengthening for blast UGent (Azer, Stijn)
63 Strengthening of filigree wideslab joints abt (Mark V., Niek P.)
64 Strengthening for impact Naples (Marco)
PART II – Reinforcing of concrete structures with FRP reinforcement
# Title Main Autors Additional contributors
7 RC MEMBER DESIGN
71 Flexural design of ribbed floor Maurizio, Ana, Lluis (see slide Maurizio)
Flexural design of continues T-beam + slab on top Maurizio, Ana, Lluis
72 Flexural design of one-way slab Reykjavik (Halldór, Eythor)
73 Flexural design of two-way slabs same team as 71
74 Shear design of beams Maurizio, Ana, Lluis
75 Long-term & durability evaluation André
8 PC MEMBER DESIGN
81 Flexural design Ted Donchev will make a first darft and then we see if we feel we can included it or if it is beyond the scope for the moment being
9 ACCIDENTAL SITUATIONS
91 Fire design Naples (Antonio B, Emidio N)
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Upcoming (4): Compendium
Compendium for Interventions on Concrete
Structures [fib T8.1 & T3.4]
1. Protection Methods
1.1. Surface protection methods
1.2. Electrochemical methods
2. Repair Methods
2.1. Material reinstatement
2.2. Concrete crack repair
3. Strengthening Methods
3.1. Strengthening existing members
3.2. Adding new structural members
3.3. Adding new systems/devices
FRP jacketing
Externally applied FRP
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
40/50
41/50
42/50
Research on structural repair
‘EXTERNALLY APPLIED REINFORCEMENT’ TECHNOLOGIES:
Surface bonded FRP (fibre reinforced polymer) reinforcement
Textile reinforced mortar overlays
Short fibre reinforced high performance mortar overlays
Post-tensioning with shape memory alloys
Strengthened structures under fire, blast or impact
→ material innovations, bond, structural behaviour, design &
modelling
43/50
FRP strengthened slabs under blast
In collaboration with RMA
44/50
DuRSAAMPhD Training Network on Durable, Reliable and Sustainable Structures with Alkali-Activated Materials
→ www.dursaam.eu
45/50
Alkali-activation technology route
→ for new concrete→ for repair of concrete by means of textile reinforced mortar
46/50
Durability, repair & maintenance of concrete structures
By-products & recycledmaterials as raw material forconcrete and concrete repairtechnologies
Residues
47/50
Currently we are developing the new AAM based TRM
01
02
03 05
04
WHAT IS
FRP &
NON-METALLIC
REINFORCEMENT
fib
TASK GROUP
T5.1
HIGHLIGTHING
SOME RUNNING
WORK
HIGHLIGTHING
THE LATEST
ACHIEVEMENT
LINK WITH
UGENT
RESEARCH
fib T5.1 members are acknowledged
for their support and their continuous
involvement in the activities.
50/50
Prof. dr. ir. Stijn Matthys
UGent DuraBUILDmaterials
DEPARTMENT OF STRUCTURAL ENGINEERING AND BUILDING MATERIALS
Technologiepark-Zwijnaarde 60, 9052 Gent
www.ugent.be/ea/structural-engineering
www.dbm.ugent.be