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3 December 2020
004854
How does RF‑STABILITY or RSBUCK determine the buckling load? According to the manual calculation, the respective buckling loads should be about 10% higher.
Answer
The partial safety factor γM for reducing the modulus of elasticity is very likely activated in RFEM/RSTAB, but is not considered in the manual calculation.
γM can be displayed and adjusted, if necessary, within the "Edit Material" dialog box, see Image 01.
Furthermore, the "Activate stiffness modifications from RFEM/RSTAB" option must be considered in General Data in the RF‑STABILITY or RSBUCK add-on module, see Iage 02.
Image 02 - Activate Stiffness Modifications in RFEM
For the effective length of 35.405 m, the second moment of area of 8,356 cm 4, the modulus of elasticity of 21,000 kN/cm², and the partial safety factor of 1.1 as a divisor, the following buckling load results (see also Image 03) according to the following formula:
Critical Load Including Partial Safety Factor
Keywords
Buckling load Critical load Manual calculation
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