What type of bar is typically used as a standard reinforcing bar?

The standard reinforcing bar commonly used in construction is the deformed bar. This type of bar features surface projections or deformations that enhance bonding with concrete, which provides greater tensile strength to the composite material. The ridges and patterns on a deformed bar create mechanical interlocking with the concrete, allowing it to better resist cracking and deformation under tensile loads.

Plain bars lack these deformations and, while they can be used in certain applications, they do not provide the same level of bond strength and are less effective in preventing slippage within the concrete. Prestressed bars are specialized types used in applications where concrete members are intentionally pre-tensioned to counteract tensile stresses. Alloy bars have specific material properties and are used for unique applications but are not the standard choice for general reinforcing purposes.

Therefore, the deformed bar, with its integral design meant for enhanced adhesion and structural integrity within concrete, is the go-to choice for reinforcing in various construction projects.