#8 Rebar Properties

Structural properties and useful information for a #8 bar

Description

A #8 bar is a american reinforcing steel designation produced under ASTM A615 or A706. It weighs 2.7 lb/ft (4 kg/m) and has a cross sectional area of 0.79 in² (510 mm²).

#8 bar is most commonly produced to have a yield strength of fy = 60ksi (414MPa), also called Grade 60, although other strengths are also available. The grade is physically shown on the rolled bars, either with a numerical grade marking or by using grade lines which are present for atleast 5 deformations. A single line denotes Grade 60, while no line would mean Grade 40 and two lines would mean Grade 75.

Properties

  • Name: #8
  • Diameter: 1 in (25.4 mm)
  • Area: 0.79 in² (510 mm²)
  • Weight: 2.7 lb/ft (4 kg/m)
  • Standard: ASTM A615 or A706
  • Typical Yield Strength: 60ksi / 414MPa
  • Typical Yield Force: 42.7 kip / 190 kN (ϕ=0.9)
MMill Symbol8Bar SizeWSteel Type60Steel GradeGrade Line

Common Questions

  • What grade is #8 rebar?

    #8 rebar is available in multiple grades, as noted by the grade line or grade marking on the bar. In the US, common grades include 60ksi and 75ksi for bar produced to ASTM A615, and grade 60ksi and 80ksi for ASTM A706. In Canada, common grades include 400 and 500 for bar produced to CSA G30.18. Higher and lower strengths are available for special applications, as well as bar produced under different steel standards and compositions.

  • Is #8 bar weldable?

    The weldability of #8 rebar depends on its grade and chemical composition. All steel rebar can be welded, but some types are more suitable than others for welding. Rebar marked with a "W" has a composition that is more readily weldable. This marking indicates the rebar meets ASTM A706 specifications in the US, or Weldable specifications for G30.18 in Canada, which control the chemical composition to ensure weldability. Weldable rebar has lower carbon equivalent, controlled carbon and manganese content, requirements for other elements like phosphorus and sulfur. Standard (non-weldable) rebar steel is generally not recommended for welding because its chemical composition hasn't been controlled for welding. It may have high carbon content that could lead to cracking, and the mechanical properties could be compromised by welding.

    If you need to weld #8 rebar, you should: Verify it's a weldable steel type with the "W" marking, use qualified welding procedures (AWS D1.4), have certified welders perform the work, consider preheating, and get engineer approval before welding structural rebar. For critical structural applications where welding is needed, it's best to specifically order Weldable rebar rather than trying to weld standard rebar.

  • How much does #8 rebar weigh?

    #8 rebar weighs approximately 2.7 lb/ft (4 kg/m).

  • What are the typical applications for #8 rebar?

    #8 rebar is commonly used in concrete construction projects like slabs, foundations, columns, walls, and other structural elements that require structural reinforcement.

  • What is the required lap splice for #8 rebar?

    See the Development Length tool to calculate development lengths for #8 rebar.

  • What is the standard length of #8 rebar?

    #8 rebar typically comes in 20, 30, 40, or 60-foot lengths, and custom lengths can be ordered from the supplier. If longer lengths are required, the rebar is usually extended with a tension lap splice or mechanical coupler.

  • What is a substitute for #8 rebar?

    See the Rebar Conversion tool to calculate equivalent bar areas and spacings for #8 rebar. Note that you should always ask for engineer approval before substituting rebar, as there are additional considerations beyond cross-sectional area.