Concrete is one of the most versatile construction materials throughout the world. However, since the early 1800s, it is known that concrete is weak in tension. Weak tensile strength combined with the brittle behaviour of concrete results in the tensile failure without warning.
This is not desirable for any construction material. Thus, concrete requires some form of tensile strength to complement its brittle behaviour.
Historically, Steel has proved to be an ideal material as a Steel Reinforcement to complement concrete because the thermal expansion of both materials is the same. In other words, when cooled or heated both concrete and steel they expand or contract equally.
Steel also bonds well with concrete. In a composite material, the bond between two materials is necessary so that it functions as a single material. The bond between the two materials is due to the chemistry of the two materials, which produces a chemical bond between them. Besides, as the water from concrete evaporates, it shrinks and grips the steel bars also making a mechanical bond.
According to ‘Madan Mehta’, ‘Walter Scarborough’ and ‘Diane Armpriest’ (Authors of Building Construction), the mechanical bond is enhanced by using reinforcing bars or rebars that have surface deformations. Because a mechanical bond is a function of the area of contact between the two materials, the surface deformations increase such area over and above increasing friction between the two, thereby increasing the bond.
To know the various types of Steel Reinforcement, first, let us understand what is Steel Reinforcement?