**2. Fibres: origin and history**

Fibres were used at least 3500 years ago to build the 57 m high hill of Aqar Quf near Baghdad through brittle matrix materials and sun-baked bricks [21]. Additionally, masonry mortar and plaster were reinforced through horsehair [22]. Similarly, cement products were reinforced through asbestos fibres for about 100 years ago. In contrast, alternate fibre types were instigated within the 1960s and 70s due to health issues related to asbestos fibres.

In the nineteenth century, the use of reinforcing rods in the tensile zone of the concrete was imposed for the low tensile strength and brittle character of concrete [23]. In addition, the incorporation of discontinuous steel reinforcing elements including metal chips, nails and wire segments into concrete was attempted through patents recently.

Romualdi and Baston [24] have investigated the steel fibres potential for steel reinforcing rods in concrete during the early 1960s in the United States. Afterwards, steel fibre reinforced concrete has been advanced through assorted experimentation, industrial application and research development. Similarly, Goldfein [25] conducted experiments with and without reinforcement using plastic fibres in concrete. Structural synthetic fibres were used explicitly by Japanese construction companies since 1997 as an alternate of steel fibre reinforcement. The expansion of structural synthetic fibres is attempted in Europe, North America and Australia.

Most applications suggest the use of fibre reinforced concrete such as refractory materials, concrete products, and road and floor slabs over the past 40 years [23].
