Determination of diameter-wall thickness ratio γ

γ = \frac{d_{0}}{2 \cdot t_{0}}

γ	Ratio of the chord member's width or diameter to the double of its wall thickness
Ψ_2,i	Beiwert für quasi-ständige Werte der veränderlichen Einwirkungen i
t₀	Wall thickness of chord cross-section

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