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Simply supported beam reactions

Static reactions and the peak sagging moment. No shear design, deflection limit or steel check.

Load case Uniform load over the whole spanPoint load at midspanPoint load at a set distance from A

Span L (m)

UDL w (kN/m)

Point load P (kN)

Distance a from A (m)

CalculateReset

Method

UDL: R_A = R_B = wL/2, M_max = wL²/8. Midspan point load: R = P/2, M = PL/4. Offset point load: R_A = Pb/L, R_B = Pa/L, M = Pab/L.

Worked UDL: 8 kN/m on 6 m gives reactions of 24 kN each and a midspan moment of 36 kN·m.

Self-weight, partial factors and lateral restraint are not included. Do not use the moment to size a beam without a competent check.

Logic: how this figure is built.

Last checked 2 October 2026. Worked figures are scenarios. See methodology and the disclaimer.