Why is reinforcing bar (rebar) coated or treated?

Reinforcing bars, commonly known as rebar, are coated or treated primarily to prevent corrosion and increase bond strength. Corrosion can severely compromise the structural integrity of reinforced concrete, leading to failures and the need for costly repairs. By applying protective coatings or treatments, the rebar is safeguarded against environmental factors such as moisture, chemicals, and chloride ions, which can lead to rust formation.

In addition to preventing corrosion, these coatings enhance the bond between the rebar and the surrounding concrete. A strong bond is essential for the effective transfer of loads and for ensuring that the concrete behaves as a composite material, ultimately contributing to the strength and durability of the overall structure. By focusing on these critical performance aspects, treating rebar serves a vital role in maintaining the longevity and safety of concrete constructions.