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Fibre reinforced concrete (FRC) is used in all areas of construction,be it industrial, commercial, institutional or residential. Such technology goes back a long way: in the Roman empire, civil engineersused animal and vegetable fibres in the construction of such wondersas the Roman Colosseum, a structure that is now nearly two thousandyears old.

TYPES OFFIBRES AND THEIRPROPERTIESAUGMENTELA RÉSISTANCERÉSIDUELLEAMÉLIORELA DUCTILITÉET LA TÉNACITÉ(RÉSISTANCE POST-FISSURATION)MEILLEURERÉPARTITIONDES CONTRAINTESMÉCANIQUESFIBRE REINFORCED CONCRETE1RENFORCERLA STRUCTUREDU BÉTON

TYPES OF FIBRESAND THEIR PROPERTIESSEVERAL TYPES OF FIBRES CAN BEINCORPORATED INTO CONCRETE. BÉTON PROVINCIALOFFERS THE FOLLOWING:PreventionSYNTHETIC MICROFIBRESMicrofibres are primarily added to concrete to reduce plastic shrinkage, which can occurat an early stage, when plastic concrete’s internal stresses are greater than its tensilestrength, that is, before the concrete adequately hardens. Specified standard quantitiesare 0.6 to 1.8 kg/m3.RetentionSYNTHETIC MACROFIBRESMacrofibres added to concrete increase its residual strength, reinforce the concrete structure, and allow mechanical stresses to be more evenly distributed in the matrix. They alsoimprove ductility and fracture toughness (post-crack resistance), impact resistance andfatigue 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 aninsubstantial effect on the number and spacing of cracks, only acting mechanically oncecracks 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-FIBRE REINFORCED CONCRETE2ment 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, quantitiescan vary between 1.8 and 11 kg/m3. Unlike microfibres, macrofibres, due to their lowspecific surface, can be used in large quantities.

RetentionMETAL FIBRESMetal fibres offer the ideal tensile strength to tear strength ratio. The performance of metalfibres depends largely on two factors:1) Their distribution (kg/m3)2) Their specifications(Length and diameter, Tensile strength,Type of anchor)The many uses of metal fibres primarily include on-ground slabs, warehouse floors that support heavy loads orendure 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 tunnelpavement.Specified standard quantities are 15 to 45 kg/m3. Depending on the fibre type, quantities can vary between15 and 150 kg/m3 for normal concretes requiring slight adjustments in their formulation.SLUMP CONTROL AND THE ADDITION OF SUPERPLASTICIZERFor all fibre types, the addition of superplasticizer is strongly recommended in order to avoid adding excesswater 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 normallyspecified at 80 /- 20 mm. For fibre reinforced concretes, it is often necessary to adjust the slump before addingfibres, in order to make the concretes more fluid. Even when fibres are added to a premix, certain fibres requirethat 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 betweenFIBRE REINFORCED CONCRETE3130 and 190 mm should be aimed for.› Canac Marquis Grenier

TECHNICAL ADVANTAGES TOFIBRE USETHE THREE-DIMENSIONAL REINFORCEMENTTHAT IS UNIFORMLY DISTRIBUTED ACROSSTHE CONCRETE MATRIX IMPROVES CONCRETE’S:direct tensilestrengthbendingstrengthimpactresistanceBY UP TOBY UP TOBY UP TO40 % *150 %*abrasionresistancea reductionof shrinkagecracksBY UP TO45 %40 %fatiguestrengthblastresistanceBY UP TO93 %› A reduction of aggregate settling, which reduces the risk of capillaries forming and thusprevents excessive bleeding;› An increase in the resistance to cracking, and a significant reduction in the lengthof cracks when they do appear;› No corrosion, in the case of synthetic fibres.* (Association béton Québec and Cement Association of Canada, 7th edition, 2004, p. 122)FIBRE REINFORCED CONCRETE4Sources› Galeries de la Capitale› Metro Plus GP› Galeries de Beauport

ECONOMIC ADVANTAGES TOFIBRE USEFibre use reduces the number of work site employees neededto install metal meshes or other reinforcements. This equalsa SUBSTANTIAL REDUCTION in the time required forconstruction.FIBRE REINFORCED CONCRETE5For example, if one considers that two to three workers caninstall, on average, 10,000 ft2 of mesh daily, this wouldmean that with the use of fibre concrete, ten days fewerwould be required for the installation of a 100,000 ft2 floor.

FINISHINGFIBRE CONCRETEFibre concrete can be finished using traditional techniques, but certain precautions should betaken to prevent fibres from showing on the surface and to minimize the risk of damage to sawkerfs 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 trowelat pronounced angles;› have performed an adequate levelling before finishing;FIBRE REINFORCED CONCRETE6› not begin finishing at a premature or late stage, nor to do the finishing by hand.

Thirty kilograms of steelfibres per cubic metreof concrete2The placementof concrete3Finishedconcrete7The pouring offibre concreteFIBRE REINFORCED CONCRETE1› SAQ Dépôt

BÉTON PROVINCIALPROVINCIALBÉTONESTUNE ENTREPRISEISA STRONGLYSOLIDEMENT IMPLANTÉEESTABLISHEDEASTERNDEPUIS PRÈSD’UN DU CANADA.YEARS'EXPERIENCE.Le groupeBétonProvincialltée estgroupeintégrédansle customers.secteur de laThecompanyforgesstrong, lastingtiesunbuilton respectwithœuvrantits partnersandconstruction.en 1960,l’entrepriseestconstammentl’affûtde meilleuresBétonProvincialFondéeis a partneryou cantrust for allyourprojects, fromà thesimplestto thesolutionspour ses clients situés au Québec et dans les Maritimes.mostcomplex.NUMBERPLANTS ABRIQUÉ55PAVING PLANTSBÉTON BITUMINEUX15158Une flotte deBÉTON RENFORCÉ DE FIBRES2525350concrete mixersbétonnières7575ready-mixedusinesconcrete plantsde béton préparé

L'ÉtapeSaguenayQuébec(Administrative office)Trois-RivièresLa yacintheMontréal-EstGranbyVille Saint-LaurentVille desLaurentidesChibougamauChapaisPiedmontEastmain 1ABéton Provincial plant locationReady-mixed concrete plantPaving plantConcrete products plantAggregateLEGENDDalhousieSaint JohnLa RomaineChandlerHavre-Saint-PierreNew CarlisleNew t-QuentinPerth-AndoverGrand lesSainte-Anne-des-MontsPort-CartierMatane (Head office)Mont-JoliRimouskiTrois-PistolesLes EscouminsForestvilleBaie-ComeauRoute 389FermontLABRADORGoose BayWabush / Labrador City

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