45M Rebar Properties

Structural properties and useful information for a 45M bar

Description

A 45M bar is a canadian reinforcing steel designation produced under CSA G30.18. It weighs 7.9 lb/ft (11.8 kg/m) and has a cross sectional area of 2.325 in² (1500 mm²).

45M bar is most commonly produced to have a yield strength of fy = 58ksi (400MPa), also called Grade 400, 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 400, while no line would mean Grade 300 and two lines would mean Grade 500.

Properties

  • Name: 45M
  • Diameter: 1.77 in (45 mm)
  • Area: 2.325 in² (1500 mm²)
  • Weight: 7.9 lb/ft (11.8 kg/m)
  • Standard: CSA G30.18
  • Typical Yield Strength: 58ksi / 400MPa
  • Typical Yield Force: 114.6 kip / 510 kN (ϕ=0.85)
MMill Symbol45Bar SizeWSteel Type400Steel GradeGrade Line

Common Questions

  • What grade is 45M rebar?

    45M 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 45M bar weldable?

    The weldability of 45M 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 45M 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 45M rebar weigh?

    45M rebar weighs approximately 7.9 lb/ft (11.8 kg/m).

  • What are the typical applications for 45M rebar?

    45M 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 45M rebar?

    See the Development Length tool to calculate development lengths for 45M rebar.

  • What is the standard length of 45M rebar?

    45M 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 45M rebar?

    See the Rebar Conversion tool to calculate equivalent bar areas and spacings for 45M rebar. Note that you should always ask for engineer approval before substituting rebar, as there are additional considerations beyond cross-sectional area.