Girder load distribution (lever rule) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Wheel 2 within first bay

Method, formulas and assumptions

• Wheel 2 offset = 0.6-1.8 = -1.2 m
• Reaction at exterior girder ΣP(S + e)/S = 1*60*((2.4+0.6)/2.4+MAX(0,(2.4+-1.2))/2.4) = 105 kN
• Distribution factor (wheels) = 105/60 = 1.75

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