Fiber for concrete from polyacrylnitrile and carbon fiber to increase durability of concrete structures.
Fiber for concrete is a fiber that is used to disperse the reinforcement of concrete, gazo – and foam concrete, polystyrene concrete, is also added to mortar, dry building mixes, etc.
Advantages polyacrylnitrile fibres, its technical characteristics, application
Technology introduction polyacrylnitrile fibers
The advantages of carbon fiber fibres, its technical characteristics, application
Fiber for concrete:
Fiber for concrete is a fiber that is used to disperse the reinforcement of concrete, gazo – and foam concrete, polystyrene concrete, is also added to mortar, dry building mixes, etc.
Fibers are made from the following materials: from polyacrylnitrile (PAN) and carbonized PAN (carbon fibre) and other traditional materials (steel, glass, basalt, polymers, polyesters, etc.).
Dispersed reinforcement improves the physico-mechanical properties of the materials throughout the volume, has a high adhesion to the cement and firmly embedded in a matrix of concrete. Fiber for concrete is an effective reinforcing additive, used in all types of concrete, when it is necessary to prevent strain cracks, resulting from mechanical stress or shrinkage (e.g., flooring). The use of fibrovolokno avoids time consuming operations on reinforcement.
Polyacrylnitrile fiber for concrete reinforcing additive of a new generation of polyacrylnitrile for any solutions on the cement or gypsum based.
Acrylic fiber for concrete is used to prevent cracking during shrinkage and in the future, making the concrete durable and impact resistant, while maintaining all the quality characteristics of concrete products. In reinforcing concrete and gypsum small decorative items polyacrylonitrile fiber plays a particularly important role, as by adding fibres of polyacrylnitrile in composition can reduce the number of defects in products to 90%. The use of polyacrylonitrile fibers allows to reduce the allocation of water through effective control of hydration, thereby reducing intrinsic load. Polyacrylonitrile fiber is resistant to all chemicals that are part of the concrete, the alkalis used in the production processes, does not corrode, is distributed uniformly (without forming clumps) throughout the volume of the composition and by reinforcing it in all directions, does not lose its durability and appearance.
Fiber for concrete made from carbon fiber (carbon fiber, HCS) – inorganic nanostructured material containing 92-99,9% carbon. Carbon fiber is produced by a stepwise heat treatment of fibers based on polyacrylonitrile (PAN), at temperatures of up to 3 200 0C. Compared to conventional structural materials (aluminum, steel, etc.) materials based on hydrocarbons have extremely high strength, fatigue resistance, modulus of elasticity, chemical and corrosion resistance, which exceeds similar indicators of steel at significantly less weight.
The advantages of fiber polyacrylnitrile:
– increases the strength of concrete in compression up to 50%,
– increases impact and fatigue strength of concrete up to 200%,
– fiber to concrete increases the strength of concrete tensile bending up to 130%,
– reduces the rate of Erasure to 40%,
– provides three-dimensional reinforcement material
– fracture toughness in terms of specific power consumption and static j-integral increases 1.5 times the static stress intensity factor by 1.2 times (at a dose of fibre 1.2 kg/m3) and 3.87 times, respectively, (at a dose of 3.6 kg/m3)
– reduces the formation of internal stresses during plastic shrinkage,
– improves wear resistance of concrete surface,
– fiber for concrete prevents delamination of the concrete mix,
– reduces the time of the primary and final hardening, the acceleration of the circulation forms,
– increases frost resistance by 40%
– increases water resistance by up to 50 %,
– reduces the risk of damage of the concrete product when removed from the mold,
– reduces cracking by reducing the length of the cracks
– reduces the risk of breaking off corners and edges,
– the destruction of concrete under load is not observed separation of the fragments, the fragments remain linked polyacrylonitrile fibers,
– polyacrylonitrile fiber treated with a special size to achieve the most effective distribution in the concrete mix.
Specifications polyacrylnitrile fibers:
Following are the characteristics of polyacrylonitrile fiber for concrete.
| Fiber | Density, g/cm3 | Diameter, µm | The modulus of elasticity, MPa | Tensile strength, MPa | Elongation at break, % | Alkali resistance |
| FibARM Fibre WB | 1,17 | 14-31 | <11 | >450 | 26 | ++ |
Application polyacrylnitrile fibers:
Polyacrylnitrile fiber for concrete used in the manufacture of:
– lightweight concrete,
– industrial floors and screeds
– building solutions,
– concrete slabs,
– paving,
– dry building mixes
– gunning,
– designs and architectural purposes.
Technology introduction polyacrylnitrile fibers:
On the basis of the obtained results suggested the following order of introduction of the components into the mixer in the manufacture of fiber-reinforced concrete mixtures in order to avoid caking of the PAN fiber:
– cement, sand,
–water at the rate of 150…160 l/m3 fiber-reinforced concrete mixture,
– coarse aggregate,
– PAN fiber in a predetermined amount,
– water in the quantity necessary for obtaining a preset water marks on the workability.
The advantages of carbon fiber fibers:
– increases the strength of concrete in compression from 40 to 60%,
– increases the strength of concrete tensile bending from 100 to 200% (depending on the strength of the matrix),
– increases impact strength up to 500%
– the strength of concrete tensile splitting from 250 to 400,
– increases the durability, resistance to abrasion and dusting to 100%,
– increases frost resistance by up to 200%,
– high adhesion to a cement matrix
– not subject to corrosion, resistance to acids, alkalis, salts,
– has a high heat-insulating characteristics,
– high temperature resistance, incombustibility,
– safe for people and the environment
– does not melt, does not decompose, the ignition temperature of 3,000 OS
– increases the durability of structures
– the possibility of reducing the working sections of structures, in some cases, reduced flow or complete refusal from the use of a rod of rebar.
Specifications carbon fiber fibre:
Following are the characteristics of carbon fiber fiber for concrete.
| Fiber | Density, g/cm3 | Diameter, µm | The modulus of elasticity, MPa | Tensile strength, MPa | Elongation at break, % | Alkali resistance |
| FibARM Fibre With | For 1.7-1.8 | 6-9 | 180-230 | 2500-2850 | 0,8 | ++ |
The use of carbon fiber fibers:
Carbon fiber fiber for concrete used in the manufacture of:
– screeds,
– design and engineering of hydraulic structures
– torkretnye,
– cellular concrete,
– manufacture of thin-walled elements and structures,
– high strength concretes.
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