Bridges · Girders & decks
Influence lines and moving loads calculator
Influence lines for reaction, shear and moment at a chosen section, and the critical position of an axle train for the maximum moment.
Standard: Simply supported beam · Müller-Breslau · axle train
Inputs in the worked example
The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.
| Input | Value | Unit |
|---|---|---|
| Span L | 20 | m |
| Section position a | 8 | m |
| Axles: load (kN), offset from first axle (m) | 60, 0 120, 3.7 120, 4.9 |
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.