GBB Event 05/06/2014 – Château de Namur

Fibre Reinforced Concrete – fib T4.1

B. ParmentierHead Div. Structures

Pantheon (-27 à 125)

From opus caementicium to concrete

From cement…J. Smeaton

L.Vicat

… J. Aspdin (ciment Portland) …

1818

[ Problem with concrete ] :

0

10

20

30

40Compression

Tension

Tensile strength

Ductility

…to (prestressed) reinforced concrete

J.L. Lambot

F. Hennebique

J. M onier T. Hyatt

E. Freysinnet

Straw as reinforcement : « Adobe »

But vegetal fibres have limitations.

Arg-é Bam (Iran | -Ve siècle)

My invention (…) consists in a composition formed by mixing two parts of coarse gravel, two parts of sand, two parts of hydraulic lime, and one part of any granular waste iron, (…)

““ “

”

Steel (fibres) as reinforcement

James Romualdi

Standardized design methods starting from 1995EC2 Building Code

Kick-off meeting

Dramix GuidelinesInfrastructuur in het

leefmilieu 4-95 Rilem TC162-TDFTest and design

methods for SFRC

2012

Océanographic Museum (Valencia, Spain)Architect : F. Candela

50 kg/m³ 6 cm

Secundary reinforcement

Ultra-High Fibre Reinforced Concrete (UHPC) (2-4% micro-fibres – fc ~150 MPa)

Stade Jean Bouin (Paris, France)Architect : R. R icciotti

reliable ?

Is

this

fib T4.1Fibre Reinforced Concrete

1. Scope

2. Terminology

3. Basic Principles

4. Principles of structural design

5. Materials6. Interface characteristics

7. Design

8. Construction

9. Conservation

10.Dismantlement, recycle and reuse

fib MC 2010

1. Scope

2. Terminology

3. Basic Principles

4. Principles of structural design

5. Materials6. Interface characteristics

7. Design8. Construction

9. Conservation

10.Dismantlement, recycle and reuse

fib MC 20105.1. Concrete5.2. Reinforcing steel5.3. Prestressing steel5.4. Prestressing systems5.5. Non-metallic reinforcement5.6. Fibres / fibre reinforced concrete

Joint chapters prepared by fib TG 8.3 “Fiber reinforced concrete” and fib TG 8.6 “Ultra high performance fiber reinforced concrete”

…7.7. Verification of safety and

serviceability of FRC structures

Post-peak behaviour (fibres only)…

P

P P

PPcr crP

crack formationcrack

crack formation

localization

Softening material Hardening material

17/63

Test methods (mainly used)

Direction tension(RILEM )

3-pt bending(EN 14651)

Round determinated plates(ASTM C1550)

18/63

Diameter 800 mmThickness 75 mm3 supports

MC 2010 Performance classesCharacterization in 3-pt bending (EN 14651)

FR,1

FR,3

0,5 1,5 3,52,5Crack opening

[mm]

Loadhsp = 125mm

L = 500 mm

20/63

MC 2010 Performance classes

Class 2a

a : 0.5 < fR3,k/fR1,k < 0.7

b : 0.7 ≤ fR3,k/fR1,k < 0.9

c : 0.9 ≤ fR3,k/fR1,k < 1.1

d : 1.1 ≤ fR3,k/fR1,k < 1.3

e : 1.3 ≤ fR3,k/fR1,k

2.0 ≤ fR1,k ≤ 2.5

1.01.52.02.53.04.05.06.07.08.0…

fR1,k [MPa]

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Ductility provided by the material (FRC/Rebars)

Ductility provided by the structural redundancy

Minimum ductility (structure)

P

PU

UPEAKSLS

Displacement

SLSP

Load

MAX

P

crack formationPCR

𝜹𝜹𝒖𝒖 ≥ 𝟐𝟐𝟐𝟐 𝜹𝜹𝑺𝑺𝑺𝑺𝑺𝑺

𝜹𝜹𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑 ≥ 𝟓𝟓 𝜹𝜹𝑺𝑺𝑺𝑺𝑺𝑺OR

ReliabilityInfluence of orientation 𝒇𝒇𝑭𝑭𝑭𝑭𝑭𝑭,𝒎𝒎𝒎𝒎𝑭𝑭 = ⁄𝒇𝒇𝑭𝑭𝑭𝑭𝑭𝑭 𝑲𝑲

L. Ferrara et al. (2010)

30 mm

23/63

ReliabilityRedistribution coefficient

𝑷𝑷𝑹𝑹𝑭𝑭 = 𝑲𝑲𝑹𝑹𝑭𝑭.𝑷𝑷(𝒇𝒇𝑭𝑭𝑭𝑭)

(𝑲𝑲𝑹𝑹𝑭𝑭)

𝑲𝑲𝑹𝑹𝑭𝑭𝑽𝑽𝑽𝑽𝟐𝟐

,𝑷𝑷𝒎𝒎𝒑𝒑𝒎𝒎𝑷𝑷𝒄𝒄𝒄𝒄

Max load

Cracking load

24/63

1. Introduction

2. Fundamentals

3. Materials

4. Mechanical properties

5. Background of design approaches

6. Background of rules in ULS and SLS

7. Durability (with or without ordinary reinforcement)

8. Severe loading conditions (blast, fire)

9. Technological aspects

10. Structural rehabilitation

11. Design examples and back calculations of full scale tests

12. Seismic resistance

FRC Bulletin (background document)

Fibres for concrete…

26/84

Material Steel fibres

Polymeric fibres (PP,PAN, PE,Aramid,PVA)

Inorganic and mineral fibres (AR glass, basalt, carbon)

Natural fibres

Blends/Cocktails

M C’10

The models are (too ?) safe

Logically, a better match is found for a/d=2.5 (solid marks)

Parmentier et al., Shear – BEFIB 2012

Test results vs. predictions

Support design assumptions by (full-scale) testing

Concentrated loads

Jack

Loadcell

Results

Published papers

30/52

BBRI - Lab. Structures bp@bbri.be