Módulo resistente viga
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The wood beam section modulus calculator is a vital tool for engineering and architectural projects. It calculates the beam's bending resistance capacity based on its cross-sectional dimensions. The formula used is W = b·h²/6, where b is the base and h is the height of the beam's cross-section.
This calculator is particularly useful during structural design, especially when planning slabs, beams, or any wooden element subjected to loads. The result helps determine if the selected section can withstand the expected stress without excessive deformation.
Note that units for b and h must be consistent (e.g., both in centimeters or meters). Additionally, the calculation does not account for factors like moisture, wood defects, or dynamic loads, which may affect the actual strength.
For accurate results, input the beam measurements and interpret the output in context. If the beam is sawn wood, consult technical standards such as NBR 7190 and NBR 14943 for validation.
Frequently asked questions
What is the purpose of a beam's section modulus?
The section modulus measures a beam's ability to resist bending, indicating whether the selected cross-section can withstand the expected structural stresses.
How does beam height affect the result?
Height (h) is squared in the formula, meaning increases in height have proportionally greater impact on the section modulus.
Can I use this calculator for concrete beams?
No. The formula is specific to rectangular wood sections. Concrete beams require different standards and material properties.
Why is the result relevant in floor slab design?
The section modulus helps dimension beams supporting slabs, ensuring they can carry self-weight and accidental loads without failure risk.