Fiber comes from latin «fibra», which means – fiber.
Fiber is a necessary component in concrete and represents individual fibers of various lengths, which are used for micro and macro reinforcement of concrete.
Fiber </ strong> is used for dispersed reinforcement of concrete structures. Dispersed reinforcement is the distribution of a large number of single microfiber in the total volume of concrete in which these two components do not react chemically to each other. At the same time, we get concrete with increased resistance to tensile, abrasion, shock and vibration loads, improved moisture and frost resistance.
The following varieties are widely used in concrete work (according to the material of manufacture ) :
- Steel fiber
- Basalt fiber
- Glass (fiberglass)
- Polyester fiber
- Polypropylene (polymer) fiber
In connection with its size, the fiber is divided into two types – MICRO and MACRO. Each type – its tasks.
Microfiber – it is a fiber in which the diameter of a single fiber does not exceed 0,3mm
Macrofiber – fiber with a single fiber diameter greater than 0,3mm
Each length of microfiber has its own purpose. There is a certain mathematical dependence of the length and diameter of the fiber in relation to the diameter of the clinker and the diameter of the sand fraction. The generally accepted world standard for fiber diameter is 18-22 microns. For reference, Chinese-made polypropylene fiber usually has a diameter of 40 microns. In this case, the number of fibers per 1 kg and therefore their effectiveness is two times lower than a certain standard.
The most common are the following lengths of synthetic polypropylene fiber:
- 2mm,3mm,4mm – used in the manufacture of Dry Construction Mixtures;
- 6mm – it used in some mixtures for self-leveling floor screeds and floor;
- 12mm – the most widely used fiber length in the world, used in the production of concrete floors, prefabricated concrete products.
- 18mm – used in the production of heavy concrete and reinforced concrete in the factory.
It is also worth paying attention to such a fiber property as elongation at break – it should not be higher than 22-25%.
Microfiber can be basalt, glass ( fiberglass ), polyester and polypropylene .
The use of fiber lengths over 18 mm in length is considered impractical, since the effectiveness of dispersed reinforcement is lost due to a sharp decrease in the number of fibers per 1 kg.
Macrofiber – mainly steel and polypropylene (polymer). Each of these types of fibers has its own advantages and disadvantages.
The main objective of macro fiber in concrete is to improve the tensile strength under tension, it is obvious that the tensile strength is 10 times less than its compressive strength. The use of macro fiber helps to significantly improve this quality of concrete.
Standard and conventional dimensions makrofibry steel and polymers:
- Single fiber diameter from 0.5mm to 1-1.3mm
- Single fiber diameter from 25mm to 65mm
The number of single fibers per 1 kg of fiber varies from 2 thousand metallic to 110 thousand polymeric . On average, steel fibers have 3-5 thousand fibers per 1 kg, polypropylene (polymer) 40-60 thousand fibers per 1 kg. Thus, polymer fiber to a greater extent saturates the volume of concrete with its fibers in comparison with metal. But the strength of steel fibers is higher than the strength of polymer.
With any type of reinforcement – macro or micro, it is very important to distribute the fiber as evenly as possible over the entire volume of concrete.
Fiber Микс®
concrete reinforcement polymer fibers
– comprehensive improvement of concrete properties
