Free Beam Stress Calculator
Determine the maximum bending stress in a beam from applied moment and section properties.
Maximum Bending Stress
89.76 MPa
Maximum Bending Stress vs Bending Moment (M)
Bending Stress in Beams
The flexure formula relates the internal bending moment to the normal stress at any fibre of the cross-section.
Formula
sigma = M c / I
M is the bending moment, c is the perpendicular distance from the neutral axis to the outermost fibre, and I is the second moment of area about the neutral axis. The result is the peak tensile or compressive stress at the extreme fibre.
Example Calculation
A steel beam with I = 8356 cm^4, depth 300 mm (c = 150 mm), under a moment of 50 kN-m.
- 01Convert moment: 50 kN-m = 50 x 10^6 N-mm
- 02Convert inertia: 8356 cm^4 = 8356 x 10^4 mm^4 = 8.356 x 10^7 mm^4
- 03sigma = (50 x 10^6 x 150) / (8.356 x 10^7)
- 04sigma = 7.5 x 10^9 / 8.356 x 10^7 = 89.76 MPa
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Beam Stress Calculation Guide: From Theory to Practice
Learn how to calculate beam stress step by step. Covers bending stress, shear stress, the flexure formula, stress distributions, and practical design checks for structural beams.