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GFRCHamzah shawyat 01203961What is FRC ?A concrete consisting of, cement, water, fine and coarse aggregate, along with discontinuous fibers.

Fiber reinforced concrete is an alternative way to reinforce concrete other then traditional steel rebar

2How its made ? - Made of traditional components of concrete such as cement, water, fine and coarse aggregate, with and addition of fiber reinforcement- The main purpose of fiber reinforced concrete it to improve flexural behavior

3Types of fibersSteel Fiber Reinforced Concrete Polypropylene Fiber Reinforced (PFR) cement mortar & concrete Glass-Fiber Reinforced Concrete Asbestos Fibers Carbon Fibers Organic Fibers

- Steel fiber come in different shapes and sizes - Depending on the application the shape of the steel fiber would be selected.- The gluing of the fibers into the bundles guarantees homogeneous distribution. A hooked end which slowly deforms during pull-outs is generally considered as the best form of anchorage4Advantages of using fiber reinforced concrete versus plain concrete Improves toughness of concreteFlexural strength is improved by up to 30% by decreasing the propagation of cracksImproves tensile strengthMore economical than steel reinforcementLess prone to corrosionGives an alternative way to reinforce concrete other then traditional steel rebar

- Improves toughness by allowing the cement to bond to the fibers causing more resistance to damaging loads and more resistant to impact- Plain concrete fails because it is a very brittle and has a low tolerance for deflections. With added fibers the concrete has a greater ability to withstand deflections b/c fibers resist the tensile forces. In result the concrete does not break immediately after the appearance of first crack.- Do to the resistance between fibers and concrete tensile strength is increased. Depends also on the types of fibers used to reinforce. Plastic/glass fibers will not improve that much while certain steel fibers can have a relatively decent improvement on tensile strength. May reduce slab thickness and eliminate use of conventional reinforcement5Steel fiberratio : 30 to 250 Diameters vary from 0.25 mm to 0.75 mm Hooks are provided at the ends to improve bond with the matrix

Polypropylene FiberCheapest & abundantly available resistant to most chemical High melting point (about 165 degrees centigrade) volume fractions between 0.5 to 15 commercially used in concrete

7Glass FiberGlass fiber is chemical inorganic fiber, obtained from molten glass of a specific composition Glass fiber is made of natural materials, so that its products are ecologically pure and not harmful to human health High bending, pulling, and pressure resistance, high temperature resistance, low hydroscope, resistance against chemical and biological influences, comparatively low density Glass fiber products have excellent electronic, heat, and sound insulation capacities

8Types of glass-fibersA-glass (close to normal glass) C-glass (resist chemical attacks) E-glass (insulation to electricity) AE-glass (alkali resistance) S-glass (high strength fiber)- Steel fiber come in different shapes and sizes - Depending on the application the shape of the steel fiber would be selected.- The gluing of the fibers into the bundles guarantees homogeneous distribution. A hooked end which slowly deforms during pull-outs is generally considered as the best form of anchorage9Properties of Glass fiber A high tensile strength (1700 N/mm^2) High modulus Impact Resistance Shear strength Water resistant Thermal conductivity Low thermal expansion Less creep with increase in time Light weight and Low density Resistance to corrosion and Fire endurance Resistance to cracks in concrete- Typically we expect a cone, cone and split, cone and shear, shear, and columnar type failure- Depending on type, shape, and fiber distribution even after a compressive failure more than less a FRC sample will keep its original shape- Like previously mentioned FRC will increases toughness and significantly improve flexural strength

10Casting of GFRCSpray-Up (very strong GFRC due to the high fiber load and long fiber length) Premix (less strength than spray-up)Hybrid Spray-up GFRC

- Typically we expect a cone, cone and split, cone and shear, shear, and columnar type failure- Depending on type, shape, and fiber distribution even after a compressive failure more than less a FRC sample will keep its original shape- Like previously mentioned FRC will increases toughness and significantly improve flexural strength

11Applications of GFRCApplications include:PipesTilt-up PanelsShotcreteSlabsCounters topsBath tubsTilesExterior Ornamentation Interior Details Landscape Furnishings Architectural projects Airfields and Runways In Rocket launch pads

12PropertiesDurabilityMade with a high content of cement and low water to cement ratioWhen properly compacted and cured, concrete with steel fibers is very durableWorkabilityAffects workabilityCompensate by adding superplasticizers

13ProductionProduction is guided and controlled mainly by the American Concrete Institute, ASTM, and various building codesProduction involves 5 Steps Determine typical Uses and Specifying FRC MaterialsMixture ProportioningBatching, Mixing, Delivery and SamplingPlacing and Finishing

1- The application will dictate the type of FRC that will be used ASM2- Selection of material will depend on the type of FRC you will need e.g. Fibers steel, glass, plastic 3- General guidance can be found in ACI 211, normally do not require adjustments to mixutre. Slump is not a good indicator for workability 4- fibers need to be added uniformly to the mixture you do not want clumps in fibers - Some are designed to be added in their water soluble packaging5- method of placing concrete that can be used for FRC are similar to thoughts uses to place Portland cement concrete such as chutes, Pumps, conveyor, tremie, shotcrete, and crane bucket- Consolidation can be done with mechanical vibration

14Summary GFRC concrete is one of the oldest methods for reinforcing concreteThe main purpose of GFRC is to increases its structural integrity and improve flexural behavior There are many different types of fiber that can be used for concrete reinforcement. Is an economical way to reinforced concrete compared to regular steel.

15ReferencesMamlouk, Michael, and John Zaniewski. Materials for Civil and Construction Engineers. Second Edition. N.J.: Pearson Hall, 2006. 576. PrintMehta, P.K., and P.J.M Monteiro. "Fibers in Concrete." University of Californa, Berkeley, 04,May,2006. Web. 1 Dec 2010.