Bending Stress Calculator
Calculate bending stress in beams.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Bending Stress Calculator
Enter the bending moment and section modulus.
- Enter bending moment in Newton-meters.
- Enter section modulus in cubic meters.
- Read the result in MPa.
About the Bending Stress Calculator
Bending stress occurs when a beam is subjected to a bending moment. It varies linearly across the cross-section: maximum at the outer fibers and zero at the neutral axis. The section modulus (S = I/c, where c is the distance to the extreme fiber) simplifies the calculation. Engineers select beam sizes by ensuring the bending stress stays below the allowable stress for the material.
Frequently Asked Questions
What is section modulus?
Section modulus S = I/c, where I is the moment of inertia and c is the distance from the neutral axis to the extreme fiber. It represents the beam's resistance to bending.
Where is bending stress maximum?
Bending stress is maximum at the top and bottom surfaces of the beam (the extreme fibers), farthest from the neutral axis.
How do I reduce bending stress?
Use a deeper beam (increases section modulus), use a stronger material, reduce the span, or add intermediate supports.