The use of fibers dates back 3500 years; it was initially used as straw to strengthen sun-baked bricks in Mesopotamia and to meet basic needs for shelter, food and clothing. In the 1950s, composite materials such as steel, glass and synthetic fibers were used to improve the properties of concrete. Fiber comes from the Latin word fibre, which is a natural or synthetic substance that is much longer than it is wide. The fibers are often used in the production of other materials. The strongest technical materials often incorporate fibers, the most common being 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, uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers, and natural fibers, each of which contributes its own unique properties to concrete. The character of fiber-reinforced concrete changes as the concrete, fibrous materials, geometries, distribution, orientation and density vary. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get Original Essay Additionally, fibers are used in concrete to control cracking due to plastic shrinkage and drying shrinkage. Furthermore, they reduce the permeability of concrete and increase the ductility of concrete elements. Some types of fibers produce greater impact, abrasion and crushing resistance in concrete. Research on new fiber-reinforced concretes continues to this day. (Excerpt from: Wikipedia) Polymer fibers are a subset of man-made fibers or synthetic fibers, which are based on chemicals rather than derived from natural materials through a purely physical process. However, polymer fiber can act as a superplasticizer additive which can result in lower water absorption rate of concrete, high level water reducer, higher strength and excellent elasticity. Therefore, an experimental investigation was conducted to determine the optimal dosage of additives and to study the effect of overdose of the mentioned additives. This elastic property of the reinforced polymer fiber in the cement-concrete mixture can produce better seismic resistance of the building or structure as it flexes for a while when the load is applied and then returns to its original position when the load is removed. The concrete mix having polymer fiber gave higher resistance results than the standard mix. (Excerpt from: Scribd) Natural fibers are abundantly available in nature and are generated or produced by plants, wood, animals, minerals and biologicals through different processes. The earliest evidence of man's use of fibers is the discovery of dyed wool and linen fibers found in a prehistoric cave in the Republic of Georgia that date back 36,000 years before the present. The use of natural fibers alters the behavior of the fibrous matrix composite after it has broken down, thereby its toughness will improve and it will have high impact resistance as well as having moderate tensile and flexural properties. Composites with natural fibers have advantages such as lower density, better thermal insulation and reduced skin irritation. Additionally, unlike glass fibers, natural fibers can be degraded by bacteria once they are no longer used. Please note: this is just a sample. Get a custom paper from our expert writers now. Get a Custom Essay Lately,.