Beam Sizing Calculator

Calculate bending moment, shear, and required section modulus for a simple beam.

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What This Calculator Does

Calculate bending moment, shear, and required section modulus for a simple beam.

It combines Span, Total Load, Beam Type to estimate Required Section Modulus (S), Max Bending Moment, Max Shear.

Formula & Method

For simply supported uniform load, maximum moment M=\frac{wL^2}{8} and max shear V=\frac{wL}{2}. Required section modulus is S=\frac{M}{F_b} (using consistent units).

Notation used in the formulas: R = Required Section Modulus (S); x_{1} = Span; x_{2} = Total Load; x_{3} = Beam Type.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

Span: Clear span of beam
Total Load: Uniformly distributed load in pounds per linear foot
Beam Type: Used directly in the calculation.

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