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MBrace Composite Strengthening SystemsFABRICSLAMINATESRESINSVAPOR PERMEABLE RESINS

MBrace CompositeStrengtheningSystemFiber reinforced polymer (FRP)composites have been used fornearly 30 years in aerospace andmanufacturing applications wherelow weight, high tensile strength,and noncorrosive structuralproperties are required. In civilengineering applications, FRP hasproven itself for years in fabricroof structures, internal concretereinforcement, deck gratings, andmost of all as externally bondedreinforcement.FRP materials are successfulin all of these applicationsbecause they exhibit low creep,FabricsThe MBrace system is “castin-place” from its two primarycomponents: fiber and polymer.The fiber is delivered to the sitein the form of dry, flexible fabricswhich are formed around thestructure and saturated withuncured epoxy, the polymercomponent.As the epoxy cures, a rigid FRPcomposite is formed that shapesitself to the structure andmonolithically bonds to thestructure via the epoxy resin.This technique, known as wetlay-up, provides flexibility,constructibility, and shortinstallation times. The result: lowerlabor costs and less downtime.LaminatesMBrace S&P Laminates are prefabricated carbon fiber reinforcedepoxy strips. The laminates arebonded to concrete using approvedlaminate epoxy adhesives. The50/1.4 and 100/1.4 laminates aresurface bonded to provide positiveand negative bending (flexure)strength.and compared with steel, arethinner, lighter, and have 10times the tensile strength. TheMBrace Composite StrengtheningSystem, an externally bondedFRP reinforcement system forconcrete and masonry structures,has proven itself in the field byexhibiting all of these properties.Near SurfaceThe MBrace S&P 10/1.4laminates are near surface mounted(NSM). NSM is a technique wherethe laminate is bonded into ashallow groove saw-cut into theconcrete. NSM provides enhancedbond and protects the laminatefrom abrasion and wear.

MBrace Typical UsesMBrace AdvantagesUpgrade load bearing capacities of concreteand masonry structures Increase bending strength of concrete beams, slabs,and walls Increase shear strength of concrete beams and walls Improve the capacity of concrete silos, pipes, andtunnels Restore capacity of concrete structures loss dueto deterioration Replace reinforcing steel lost to corrosion Replace damaged post-tensioning tendons Provide confinement to concrete repairsCorrect design/construction errors Substitute missing reinforcing steelSeismic Retrofit Improve strength and ductility of concrete columns Provide additional confinement and strength toconcrete connections Prevent brittle shear failures of concrete beamsand wallsHigh strength, high stiffnessLightweightHighly durable, non-corrosiveLow installation timeCan be installed in areas with limited accessEasy to concealForms around complex surface shapes

MBrace Fabric System ComponentsMBrace PrimerLow viscosity to penetrate concrete pore structureMBrace PuttyHigh viscosity epoxy paste for surface levelingMBrace SaturantLow sag epoxy for encapsulating the fibersCONCRETE SUBSTRATEPRIMEREPOXY PUTTY FILLER1ST RESIN COATFIBER REINFORCEMENT2ND RESIN COATINGPROTECTIVE COATINGMBrace Fiber ReinforcementsCarbon, E-Glass, and Aramid fiber fabricsMBrace TopcoatsHigh viscosity epoxy paste for surface leveling Topcoat ATXLatex topcoat with color/texture to match concrete Topcoat FRLFire-Resistant topcoat to improve burn characteristicsMBrace ResicemMBrace Resicem components are vapor permeable. This allows totalcoverage or encapsulation while still allowing the concrete substrateto breathe. Vapor permeable VOC Compliant Patented technology (US patent #: 6,457 289 B1) New North American technology Cement modified epoxy matrix Application to substrates with up to 12% moisture-content Not to be used with E-GlassMBrace AK 60 Aramid Fiber High strength Excellent chemical resistance Low conductivity and creep rupture Usable temperature range /- 350 F Excellent impact resistanceMBrace CF 130 & CF160High Strength Carbon Fiber Very high strength and stiffness Excellent moisture and chemical resistance Highly resistant to fatigue and creep ruptureMBrace CF 530 Carbon Fiber Fabric High strength, very high stiffness Excellent moisture and chemical resistance Highly resistant to fatigue and creep ruptureMBrace EG 900 E-Glass Fiber High strength Relatively high elongation to failure Low conductivity MBrace S&P Laminates Fast and easy installation Shipped in rolls or cut lengths Durable Light weight High-strength to weight ratioULTIMATETENSILESTRENGTHTENSILEMODULUS OFELASTICITY3/8" (10mm) 0.055 in.(1.4 mm)390 ksi(2690 MPa)23,000 ksi(160 GPa)1.67%Pre-fabricatedCarbon/Epoxy2" (50mm)0.055 in.(1.4 mm)390 ksi(2690 MPa)23,000 ksi(160 GPa)1.67%Pre-fabricatedCarbon/Epoxy4" (100mm) 0.055 in.(1.4 mm)390 ksi(2690 MPa)23,000 ksi(160 GPa)1.67%MBrace TURESTRAIN

Repair any large areas of spalled,delaminated, or otherwise deterioratedareas of the concrete substrate andinject any existing cracks in thesubstrate. Profile the concrete surfaceby abrasive blasting, water blasting, ordisc grinding.Ease of InstallationThe MBrace Composite StrengtheningSystem is installed by trained, qualifiedapplicators. Although the installationprocess will vary depending on thespecifics of the project, there are a number ofcommon steps that are followed.ULTIMATETENSILESTRENGTHTENSILEMODULUS OF RUPTUREELASTICITYSTRAINMBrace Fiber PRODUCTReinforcement ARCHITECTURENOMINALTHICKNESSCF 130High StrengthCarbon Fiber9 oz. Unidirectionalfabric0.0065 in/ply 550 ksi33,000 ksi(0.165 mm/ply) (3800 MPa) (227 GPa)1.67%CF 160High StrengthCarbon Fiber18 oz. Unidirectional 0.0130 in/ply 550 ksi33,000 ksifabric(0.330 mm/ply) (3800 MPa) (227 GPa)1.67%CF 530High ModulusCarbon Fiber9 oz. Unidirectionalfabric0.0065 in/ply 510 ksi54,000 ksi(0.165 mm/ply) (3500 MPa) (373 GPa)0.94%EG900E-glass Fiber27 oz. Unidirectional 0.0139 in/ply 220 ksi10,500 ksifabric(0.353 mm/ply) (1520 MPa) (72.4 GPa)2.10%AK 60Aramid Fiber18 oz. Unidirectional 0.0110 in/ply 290 ksi17,400 ksifabric(0.279 mm/ply) (2000 MPa) (120 GPa)1.67%1. Apply the surface primer using a mediumnap roller.4. Cut the dry fiber fabric into the properwidth and length using shears of utilityknife.2. Apply the putty using a trowel to leveluneven surfaces.5. Set the dry fiber fabric into wet saturantand press to the surface using a rib(defoaming) roller. Apply a second layer ofsaturant to fully encapsulate fibers.3. Apply a first layer of saturant (resin)using a medium nap roller.6. Repeat saturant/fiber/saturant layers asneeded. Apply optional MBrace topcoat.Once the resin cures, the final result isa solid fiber reinforced polymer (FRP)laminate that is bonded to the surfaceof the structure. The system generallyachieves sufficient cure to receive loadwithin 24 hours (depending on ambienttemperatures).

American Concrete Institute (ACI) just recently publishedits first recommendations on the use of FRP systemsfor strengthening concrete. Based largely on the 1997MBrace Design Guide, ACI 440.2R-02 is a comprehensivedocument covering the design, construction and qualitycontrol aspects of using FRP systems.Flexural StrengtheningMBrace reinforcement may be used to supplement thebending strength of beams, slabs, walls, and other flexuralelements. The bending capacity of reinforced, prestressed,and post-tensioned members can be increased by up to70%. In these applications, the MBrace system is installedalong the length of the member similar to longitudinal steelreinforcement.MBrace can be applied to concreteand masonry walls to increase theirresistance to out-of-plane loads. Thisincludes loads due to wind, soilpressure, fluid pressure in tanks,and blast loading.In negative moment regions, thereinforcement may be placed onthe top of the member for increasedcapacity. The thin profile of theinstalled MBrace system allowsfor carpet, tile, and other flooringfinishes to be installed over the systemwithout any significant change in floorelevation.Shear StrengtheningMBrace reinforcement may be used to increase the shearcapacity of concrete beams, columns, and other members.The shear capacity of members can be increased as muchas 100% and more ductile behavior can be promoted byproviding adequate shear reinforcement. In this application,the MBrace reinforcement is oriented transversely similar tosteel stirrups, ties, or hoops.MBrace shear reinforcement canbe placed as individual strips ofreinforcement. In some cases, thisallows holes to be cut in the flange orslab so that the reinforcement can bewrapped around the section entirely.MBrace can also be wrapped aroundcolumns to provide additional shearcapacity to resist seismic loads, windloads, or movement of adjoiningmembers (such as creep and shrinkageof adjoining beams).“U” wrapping — simply wrapping thesides and bottom of the section— canincrease the shear strength of beamsin high shear zones. An additional 1 to2 kips (for every inch of beam depth)or 200 to 400 N (for every millimeter orbeam depth) of shear capacity can begained by “U” wrapping with MBrace reinforcement.One of the distinct advantages of usingMBrace reinforcement on slabs isthe ability to easily run reinforcementin two directions for two-way slabs.Due to the thin profile of the MBrace fabrics, no special detailing is requiredat the intersection of two strips onreinforcement.The lightweight, flexible nature of theMBrace system allows overheadinstallations on beam and slab soffitsto be simple, cost-effective, and muchsafer than using bonded steel plates.

ConfinementWhen confined with external FRP reinforcement, concrete’scompressive behavior is dramatically improved. Thecompressive load carrying capacity of concrete can benearly doubled using FRP confinement, and the deformationcapacity can be increased ten fold. This allows concretestructures to be retrofitted for improved displacement ductilityin seismic events. FRP confinement can also be used toclamp existing lap splices in columns — a common problemin seismic regions where tension splices are needed but onlycompression splices are provided.Other ApplicationsMBrace reinforcement is extremely versatile. Use itexternally anywhere additional reinforcement is needed. Blast mitigation for concrete and masonry walls Strengthen for pressure in pipes, silos, and tanks Reinforce around slab and wall cutouts Strengthening domes, tunnels, and chimneys