Concrete is undoubtedly the leading construction material worldwide. Plain concrete, however, has a low tensile strength, which will not suffice for most constructions. The way to boost your construction’s tensile strength is through steel reinforcement. This also has high compression strength, which will minimise the risk of cracks when concrete is is exposed to high tension loads.
A company that provides steel pipe products will have several reinforcement options for your concrete construction in the form of reinforcement bars or rebars. The surfaces of some of these reinforcement bars are patterned to enhance their proper bond to the surrounding concrete structure. The following are the different types of reinforcement bars.
Hot-Rolled Deformed Bars
These are the most commonly used for reinforcing concrete structures. The hot rolling process of the bars leaves specific deformations on the surfaces, which look like ribs. These help enhance the adherence of the bars to concrete. Hot-rolled deformed steel bars have an overall yield strength of 60000psi.
Cold-Worked Steel Bars
These are manufactured through the cold working of hot-rolled steel bars. During the process, steel bars are twisted and drawn at room temperature. Since the bars do not go through plastic yields, they have less flexibility than hot-rolled deformed bars. Cold-worked steel bars are used in projects in which straightness and low tolerance are the significant concerns. They have similar yield strength to that of hot-rolled bars.
Mild Steel Plain Bars
Unlike other rebars, these have no surface enhancements but rather hooks on their ends to boost their adherence to concrete. Mild steel plain bars have tensile yield strength of 40000psi. They are generally used in small projects that have a minimal budget.
Prestressing Steel Bars
These rebars come in the form of tendons or strands, which are made of seven, two or three wire strands. The most common rebars feature six wire strands wound around a seventh wire with a slightly larger diameter than the others to form a helical shape. Prestressing steel bars have tensile yield strengths of 25000 to 27000psi. This high tensile strength enables the reinforcing bars to strengthen your concrete even with material losses. As such, they are used in large buildings and bridges where this strength is essential.
Most contractors assume that any metal will offer as much reinforcement for their construction as the above reinforcement bars. Other types of metal, however, might affect the expansion and contraction of concrete. Steel and concrete, on the other hand, have the same thermal expansion coefficient and will undergo similar changes. Therefore, the bars above will not hinder your concrete structure’s movements.
Moreover, steel bars are durable and readily available and can be recycled and manufactured to different sizes to suit various applications. They will also not float around in your concrete structure. The primary drawback of steel rebars used to be their susceptibility to corrosion. Fortunately, this is not an issue anymore with the availability of galvanised, glass fibre-reinforced, carbon and epoxy-coated steel bars. So there is no reason to choose another reinforcement option for your construction other than steel.