The Use of Fibers History

The use of fibers started way back 3500 years ago; it was first used as straw to reinforce sun-baked bricks in Mesopotamia and was used in order to meet the basic requirement of shelter, food and clothes. In 1950s, composite materials like steel, glass and synthetic fibers have been used to improve the properties of concrete. Fiber came from the Latin word fibra, which is a natural or synthetic substance that is way longer in length than its width. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, the most common are carbon fiber and ultra-high-molecular-weight polyethylene. Fiber-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers and natural fibers, each of which is contributing its unique properties to the concrete. The character of fiber-reinforced concrete changes with varying concretes, fiber materials, geometries, distribution, orientation, and densities.

In addition, fibers are used in concrete to control cracking due to plastic shrinkage and to drying shrinkage. Also, they reduce the permeability of concrete and increase the ductility of concrete elements. Some types of fibers produce greater impact, abrasion, and shatter-resistance in concrete. The research into new fiber-reinforced concrete continues up to the present date. (Retrieved from: Wikipedia)

Polymer fibers are a subset of man-made fibers or synthetic fibers, which are based on chemicals rather than arising from natural materials by a purely physical process. However, polymer fiber may serve as a superplasticizer admixture which may result to concrete’s lower rate of water absorption, high-range water reducer, greater strength and excellent in elasticity. Hence, an experimental investigation was conducted to determine the optimum dosage for the admixtures and to study the effect of over dosage of the mentioned admixtures. This elastic property of the polymer fiber reinforced in cement-concrete mix may produce better earthquake resistance of the building or structure as it deflects for a while as the load is applied and then returns to its original position as the load is removed. Concrete mix having polymer fiber gave greater strength results than the standard mix. (Retrieved from: Scribd)

Natural fibers are abundantly available in nature and are generated or produced by plants, wood, animal, mineral and biological through different processes. The earliest evidence of humans using fibers is the discovery of wool and dyed flax fibers found in a prehistoric cave in the Republic of Georgia that date back to 36,000 before the present. The use of natural fibres makes alteration in the behavior of fibre-matrix composite after it has cracked, with that, its toughness will improve and have high impact strength aside from having moderate tensile and flexural properties. Composites with natural fibers have advantages such as lower density, better thermal insulation, and reduced skin irritation. Further, unlike glass fibers, natural fibers can be broken down by bacteria once they are no longer in use.

Latterly, the abundance of interest in concrete leads to the most frequently used construction material in the world. Concrete is the world’s most used construction material. Comparing the Reinforced Cement Concrete and Fiber Reinforced Concrete, the latter one is more efficient for the reason that the RCC lasts for only 6 to 8 years and the structure itself for only 60 to 80 years. The fiber reinforcement is effective in improving the toughness, shrinkage and durability characteristics of concrete. From the most commonly used fibers, easily available and low cost natural fibers can be used. In spite of many of the researchers of using different natural fibers to improve the different properties of light weight concrete still required a lot of experiments as well as investigations. The present discoveries consist of the comparison of different natural fibers. The slump, compressive strength as well as flexural strength were compared for these natural fibers. A new approach of utilizing the water retention capacity of plant-based fibres to produce high performance cement composites through the internal curing technology should also be explored.