Section Modulus
Definition
A geometric property relating bending moment to bending stress: S = I/c, where I is moment of inertia and c is distance from neutral axis to extreme fiber. Used in the bending stress formula: σ = M/S.
Practical Note
Higher S means lower stress for the same moment. For symmetric sections, S_top = S_bottom. For asymmetric sections like T-beams, calculate S for both top and bottom fibers.
Related Calculators
📐Moment of Inertia Calculator
Calculate moment of inertia (second moment of area), section modulus, and radius of gyration for common cross-sectional shapes including rectangles, circles, I-beams, and channels.
📐Beam Deflection Calculator
Calculate maximum deflection, bending moment, and stress for simply supported and cantilever beams. Includes 3D visualization.