A heavier fabrication of welded wire fabric can be used in walls and structural floor slabs. It can be used in slab-on-ground slabs where the ground has been well compacted. Welded wire fabric (WWF) is made from a series of steel wires arranged at right angles and electrically welded at all steel wire crossings. Many consider carbon steel rebars to be the best option in all other types of construction, however. This is the most common type of rebar and is sometimes referred to as a “black bar.” It’s extremely versatile but it corrodes more easily than other types, making it inappropriate in areas that are subject to high humidity or in structures that are frequently exposed to water. When a single line is present, it represents a 60,000-psi bar. If the rebar contains two lines, it indicates that the rebar was rolled into the 75,000-psi bars. High-strength reinforcing steel uses a continuous line system to show steel grade. Lower-strength reinforcing steel bars have only three marks that identify the mill that produced the bar, the rebar size, and the type of steel used.

A symbol identifying the manufacturer that rolled the bar must be included: This is usually a single letter or a plain symbol.ĬHECK OUT Different Types of Reinforced Concrete.

The grade indicates the rebar yield strength.

The rebar grade identification must be cited: This is either 60 or 75, or metric 420 or 520.

For example, “N” means the bar was rolled from a new billet, “W” stands for weldable steel, and “A” designates rolled axle steel.

The type of steel symbol must be noted.

The American Society for Testing and Materials (ASTM) has created a standard identification ruling that all rebars must comply with: Rebars are required to contain some sort of identification that can be used to identify the mill that produced the reinforcing steel bar. Most rebars are rolled from new steel billets, but others are rolled from steel debris or railroad rails. Reinforcing bars are hot-rolled using different steel materials. Rebar: Reinforcing Steel Bar Specifications

The pattern on a deformed bar isn’t specified, but the spacing and the height of the “bumps” is regulated.

The deformed pattern on a rebar helps the concrete adhere to the reinforcing steel surface.

Properties of reinforcing steel