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Simply Supported Beam
Reactions, shear force and bending moment diagrams for a simply supported beam with a point load and a full-span UDL. Optional elastic deflection.
Worked example: UDL on a simply supported beam
L = 8 m, w = 10 kN/m, E = 200 GPa, I = 100 × 10⁶ mm⁴
R = wL/2 = 10 × 8 / 2 = 40 kN M = wL²/8 = 10 × 8² / 8 = 80 kN·m EI = 200 × 100 = 20 000 kN·m² δ = 5wL⁴/(384EI) = 5 × 10 × 8⁴ / (384 × 20 000) = 0.02667 m = 26.67 mm
Frequently asked questions
Can I add more than one point load?
The free version takes one point load plus a full-span UDL. Multiple loads and load combinations belong in the premium tools.
Why is deflection only shown when I enter E and I?
Deflection depends on the member stiffness EI. The calculator never assumes a stiffness for you.
Are load factors applied?
No. Enter the load values you want analysed — characteristic or factored — and the results are action effects for those values.
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