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What is the maximum bending moment for an H beam?

The maximum bending moment that an H-beam (also known as an I-beam or W-beam) can withstand depends on various factors, including its dimensions, material properties, and the applied loads.

Top 4 information for calculating the maximum bending moment for an H-beam

To calculate the maximum bending moment for an H-beam, you would typically need to know the following information:

  1. The dimensions of the H-beam, including the height (h), flange width (b), and flange thickness (t).
  2. The material properties of the H-beam, such as the yield strength (often denoted as “fy”).
  3. The span or length of the beam between the supports.
  4. The type and distribution of loads applied to the beam, such as point loads, distributed loads, or a combination of both.
Hard Way Bend I Beams/Rolling Beam With PBH Section Bending Machine

The maximum bending moment for an h beam formula

Once you have this information, you can use structural engineering principles and equations to calculate the maximum bending moment. The maximum bending moment usually occurs at the point on the beam where the bending stress is the highest. The formula for calculating bending stress (σ) is:

σ = (M * c) / I


  • σ is the bending stress.
  • M is the bending moment.
  • c is the distance from the neutral axis to the outermost fiber of the beam (the distance from the center of the beam to the edge of the flange).
  • I is the moment of inertia of the beam’s cross-section, which depends on the beam’s dimensions.

To find the maximum bending moment, you would calculate the bending stress at different points along the beam’s span and identify the point where the bending stress is the highest. The maximum allowable bending stress (usually based on the material’s yield strength) is used to determine the maximum bending moment the beam can withstand.

Final Words

It’s important to consult with a structural engineer or reference relevant design codes and standards (e.g., AISC for steel beams) to ensure the H-beam is properly sized and designed for the specific application and loading conditions. The maximum bending moment can vary significantly depending on these factors.