Beam Check

Statics Preliminary estimate

Moment, shear, deflection and bending stress for a simply-supported beam — with an optional allowable-stress check for quick preliminary sizing.

Results update as you type. These are educational estimates — confirm against the governing code and a licensed engineer before design use.

Method & references

A simply-supported beam under a uniform or central point load, from statics:

Uniform: M = wL²/8, V = wL/2, Δ = 5wL⁴ / (384·E·I)

Point (center): M = PL/4, V = P/2, Δ = PL³ / (48·E·I)

Bending stress is f_b = M / S. If an allowable bending stress F_b is provided, the tool reports the demand/capacity ratio f_b/F_b and whether the section is adequate. Defaults shown are for a steel section (E = 29,000 ksi); adjust E, I, and S for your material and shape.

This is an elastic, single-span check for preliminary sizing only — it does not cover lateral-torsional buckling, shear capacity, combined loading, or code load factors.