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FAQ 004856 | How is the buckling load determined in RSBUCK if the most unfavorable value is transferred from RSTAB for a non-constant axial force distribution?
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How is the buckling load determined in RSBUCK if the most unfavorable value is transferred from RSTAB for a non-constant axial force distribution?Answer
Basically, the buckling load is determined as follows when activating the option to transfer the most unfavorable value of the axial force for a non-constant distribution:
Critical load factor * most unfavorable value of the axial force = buckling load
However, the most unfavorable value refers to the member part, not to the entire member. The value of the most unfavorable axial force of the entire member is only assumed as the most unfavorable value if "1" is selected for "Internal Member Partition for", see Image 01.
Image 01 - Options and Internal Member Partition in RSBUCK
Otherwise, the mean value is first determined internally from the most unfavorable values of the respective member partitions. The following diagram shows the most unfavorable value for two member parts from the axial force distribution in the following image:
(60 kN + 30 kN) / 2 = 45 kN
Image 02 - Example: Non-Constant Axial Force Distribution Within Member
Thus, the following buckling load results for the first buckling mode in this example:
2.429 * 45 kN = 109.3 kN
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Dlubal FAQ Buckling load Critical load Most unfavorable Value Frequently Asked Question FAQ about Dlubal Question and Answer about Dlubal
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This technical article analyzes the effects of the connection stiffness on the determination of internal forces as well as the design of connections using the example of a two-story, double-spanned steel frame.
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