How is a simple beam with a uniformly distributed load checked for strength?

How is a simple beam with a uniformly distributed load checked for strength?

• A. By calculating bending moment capacity, verifying section modulus and full strength of the chosen cross-section, comparing with factored loads.
• B. By only checking deflection limits.
• C. By ignoring material properties and focusing on aesthetics.
• D. By verifying only service loads.

Answer: (A)

Strength for a simple beam under a uniformly distributed load is about making sure the cross-section can resist the bending caused by that load, using the section’s ability to resist bending and the material’s strength, and then checking this against factored loads. For a simple, simply supported beam with a uniform load, the maximum bending moment is wL^2/8. The beam’s capacity to resist that moment depends on its section modulus and the material’s bending strength. In design terms, you compare the factored bending moment from the load (the moment you get after applying load factors) with the cross-section’s bending capacity derived from its section modulus and the material’s properties. If the factored moment is within the cross-section’s capacity, the strength check passes. Deflection or serviceability checks are separate and address stiffness and deformation, not the strength of the cross-section. Choosing to ignore material properties or to check only service loads would not properly verify the beam’s strength.

Strength for a simple beam under a uniformly distributed load is about making sure the cross-section can resist the bending caused by that load, using the section’s ability to resist bending and the material’s strength, and then checking this against factored loads.

For a simple, simply supported beam with a uniform load, the maximum bending moment is wL^2/8. The beam’s capacity to resist that moment depends on its section modulus and the material’s bending strength. In design terms, you compare the factored bending moment from the load (the moment you get after applying load factors) with the cross-section’s bending capacity derived from its section modulus and the material’s properties. If the factored moment is within the cross-section’s capacity, the strength check passes.

Deflection or serviceability checks are separate and address stiffness and deformation, not the strength of the cross-section. Choosing to ignore material properties or to check only service loads would not properly verify the beam’s strength.