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Fibre reinforced concrete (FRC) is used in all areas of construction, be it industrial, commercial, institutional or residential. Such tech-nology goes back a long way: in the Roman empire, civil engineers used animal and vegetable fibres in the construction of such wonders as the Roman Colosseum, a structure that is now nearly two thousand years old.
TYPES OF FIBRES AND THEIR PROPERTIES
AUGMENTE LA RÉSISTANCE RÉSIDUELLE
RENFORCER LA STRUCTURE DU BÉTON
MEILLEURE RÉPARTITION DES CONTRAINTES MÉCANIQUES
AMÉLIORE LA DUCTILITÉ ET LA TÉNACITÉ (RÉSISTANCE POST-FISSURATION)
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SYNTHETIC MICROFIBRESMicrofibres are primarily added to concrete to reduce plastic shrinkage, which can occur
at an early stage, when plastic concrete’s internal stresses are greater than its tensile
strength, that is, before the concrete adequately hardens. Specified standard quantities
are 0.6 to 1.8 kg/m3.
SYNTHETIC MACROFIBRESMacrofibres added to concrete increase its residual strength, reinforce the concrete struc-
ture, and allow mechanical stresses to be more evenly distributed in the matrix. They also
improve ductility and fracture toughness (post-crack resistance), impact resistance and
fatigue strength.
Synthetic macrofibres can replace metal mesh and, in some cases, reinforcement beams,
in on-ground slabs, metal bridging and insulating formwork. Reinforcement beams have an
insubstantial effect on the number and spacing of cracks, only acting mechanically once
cracks are created. Steel reinforcements and mesh are reactive rather than preventative,
having no effect until a crack appears.
Through research and development, we have applied a technology of structural reinforce-
ment to the following:
- On-ground slabs - Shotcrete
- Composite slabs - Precast concrete (septic tanks, barriers, etc.)
The specified standard quantities are 2 to 9 kg/m3. Depending on the fibre type, quantities
can vary between 1.8 and 11 kg/m3. Unlike microfibres, macrofibres, due to their low
specific surface, can be used in large quantities.
TYPES OF FIBRES AND THEIR PROPERTIES
SEVERAL TYPES OF FIBRES CAN BE INCORPORATED INTO CONCRETE. BÉTON PROVINCIAL OFFERS THE FOLLOWING:
Prevention
Retention
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METAL FIBRES
Metal fibres offer the ideal tensile strength to tear strength ratio. The performance of metal
fibres depends largely on two factors:
1) Their distribution (kg/m3) 2) Their specifications
(Length and diameter, Tensile strength,
Type of anchor)
Retention
The many uses of metal fibres primarily include on-ground slabs, warehouse floors that support heavy loads or
endure large impacts, aerated concrete roofing components, roadway paving, bridge decks, refractory materials
(stainless steel), the design of precast elements, heat-resistant and explosion-resistant structures, and tunnel
pavement.
Specified standard quantities are 15 to 45 kg/m3. Depending on the fibre type, quantities can vary between
15 and 150 kg/m3 for normal concretes requiring slight adjustments in their formulation.
SLUMP CONTROL AND THE ADDITION OF SUPERPLASTICIZER
For all fibre types, the addition of superplasticizer is strongly recommended in order to avoid adding excess
water to the mix at the work site, and to render the concrete more fluid before fibres are inserted.
Slump control is also very important: the slump for a basic mix of non-fibre reinforced concrete is normally
specified at 80 +/- 20 mm. For fibre reinforced concretes, it is often necessary to adjust the slump before adding
fibres, in order to make the concretes more fluid. Even when fibres are added to a premix, certain fibres require
that the slump/fluidity be increased in order obtain a more even mix.
For example, if the steel fibre concentration is to be between 20 and 40 kg/m3, an initial slump of between
130 and 190 mm should be aimed for.
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› Canac Marquis Grenier
TECHNICAL ADVANTAGES TO
FIBRE USE
› A reduction of aggregate settling, which reduces the risk of capillaries forming and thus prevents excessive bleeding;
› An increase in the resistance to cracking, and a significant reduction in the length of cracks when they do appear;
› No corrosion, in the case of synthetic fibres.
fatigue strength
blast resistance
direct tensile strength
BY UP TO
40 % *
THE THREE-DIMENSIONAL REINFORCEMENT THAT IS UNIFORMLY DISTRIBUTED ACROSS THE CONCRETE MATRIX IMPROVES CONCRETE’S:
bending strength
BY UP TO
150 %*
impact resistance
BY UP TO
40 %
abrasion resistance
BY UP TO
45 %
a reduction of shrinkage
cracks BY UP TO
93 %
Sources * (Association béton Québec and Cement Association of Canada, 7th edition, 2004, p. 122)
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› Galeries de la Capitale › Metro Plus GP › Galeries de Beauport
Fibre use reduces the number of work site employees needed to install metal meshes or other reinforcements. This equals a SUBSTANTIAL REDUCTION in the time required for construction.
For example, if one considers that two to three workers can install, on average, 10,000 ft2 of mesh daily, this would mean that with the use of fibre concrete, ten days fewer would be required for the installation of a 100,000 ft2 floor.
ECONOMIC ADVANTAGES TO
FIBRE USE
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FINISHING FIBRE CONCRETE
Fibre concrete can be finished using traditional techniques, but certain precautions should be
taken to prevent fibres from showing on the surface and to minimize the risk of damage to saw
kerfs when sawn control joints are being placed. Such precautions include:
› using a double trowel;
› placing the trowel as flat as possible against the surface of the concrete;
› bull floating after screeding;
› using screeds and laser equipment.
It is important to:
› avoid the use, as much as possible, of a single trowel finishing machine and a trowel at pronounced angles;
› have performed an adequate levelling before finishing;
› not begin finishing at a premature or late stage, nor to do the finishing by hand.
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Thirty kilograms of steel fibres per cubic metre
of concrete
The pouring of fibre concrete
› SAQ Dépôt
The placement of concrete
Finished concrete1 2 3
BÉTON PROVINCIALEST UNE ENTREPRISESOLIDEMENT IMPLANTÉE DEPUIS PRÈS D’UN DEMI-SIÈCLE DANS L’EST DU CANADA.Le groupe Béton Provincial ltée est un groupe intégré œuvrant dans le secteur de la
construction. Fondée en 1960, l’entreprise est constamment à l’affût de meilleures
solutions pour ses clients situés au Québec et dans les Maritimes.
350Une flotte de
bétonnières
75usines
de béton préparé
25 5
15
NOMBRE D’USINES PAR CATÉGORIES
CARRIÈRES
BÉTON PRÉFABRIQUÉ
BÉTON BITUMINEUX
BÉTON PROVINCIAL IS A STRONGLY ESTABLISHED EASTERN CANADIAN COMPANY WITH CLOSE TO 50 YEARS' EXPERIENCE.The company forges strong, lasting ties built on respect with its partners and customers.
Béton Provincial is a partner you can trust for all your projects, from the simplest to the
most complex.
350concrete mixers
75ready-mixedconcrete plants
25 5
15
NUMBER OF PLANTS BY CATEGORY
QUARRIES
PRECAST CONCRETE PRODUCTS PLANTS
PAVING PLANTS
BÉ
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N R
EN
FO
RC
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8
BÉTON PROVINCIALEST UNE ENTREPRISESOLIDEMENT IMPLANTÉE DEPUIS PRÈS D’UN DEMI-SIÈCLE DANS L’EST DU CANADA.Le groupe Béton Provincial ltée est un groupe intégré œuvrant dans le secteur de la
construction. Fondée en 1960, l’entreprise est constamment à l’affût de meilleures
solutions pour ses clients situés au Québec et dans les Maritimes.
350Une flotte de
bétonnières
75usines
de béton préparé
25 5
15
NOMBRE D’USINES PAR CATÉGORIES
CARRIÈRES
BÉTON PRÉFABRIQUÉ
BÉTON BITUMINEUX
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