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Load combinations

It is unlikely that full snow, full wind and full imposed load occur at the same time. So one variable load is taken as leading with its full value, while the others are reduced by a combination factor ψ. All combinations are tried, and the worst one is used.

F_d = 1.2\,G_k + 1.5\,Q_{k,1} + 1.5\,\psi_0\,Q_{k,2}

one leading and one accompanying load

Symbols

$Q_{k,1}$	leading variable load	kN
$Q_{k,2}$	accompanying variable load	kN
$\psi_0$	combination factor

Example

Snow 30 kN leading, wind 20 kN with $\psi_0 = 0.6$ , $G_k = 100$ kN:

$120 + 45 + 18 = 183$ kN.

Swap which load is leading, and use the combination that gives the largest value.

Practise loads and load combinations for free →

← Load factors · U-value →

Part of Building and Structures: Loads and load combinations.