Simply Supported Beam Calculation Guide
1. Define the span
Set the simply supported span L from the left support at x = 0 to the right support at x = L.
2. Add supported loads
Add one or more point loads and/or uniform distributed loads. A UDL may cover the full span or only a partial interval.
3. Calculate reactions
The verified beam mechanics determine the left and right support reactions from vertical-force and moment equilibrium.
4. Review shear and bending moment
Review maximum and minimum shear and bending moment values with their reported locations. Sagging bending moment is positive.
5. Add E and I only when deflection is needed
If both Young's modulus E and second moment of area I are supplied, the calculator also reports deflection. Downward deflection is negative.
6. Interpret critical locations correctly
criticalLocationsM is a non-exhaustive engineering review set. It includes inherited extrema and load/UDL breakpoints, but is not every analytical root or every one-sided discontinuity limit.
Scope limits
This guide covers simply supported beams with point loads and uniform distributed loads only. It does not cover cantilevers, multi-span beams, triangular/trapezoidal loads, material strength, or code-design checks.
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