Understanding Buckling: The Impact of Moments vs Applied Forces

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A moment about the end of a structure cannot cause buckling; buckling is driven by applied forces rather than moments. The deflection equation indicates that the moment is proportional to lateral deflection, but it does not function as a direct cause of buckling. Localized buckling can occur after initial deformation, potentially leading to structural failure. However, the primary concern should be bending stresses resulting from deflection. Understanding these dynamics is crucial for assessing structural integrity.
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Can a moment about the end of something cause buckling or does it need to be an applied force?

For instance the uploaded image

Thanks!
 

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Although I do not know your end conditions from your drawing, a end applied moment cannot cause buckling. Buckling arise from the deflection equation E I y'' = M where M is proportional to the lateral deflection, y. In your problem, M, shown above, is just your end applied load and is never a function of the deflection.
 
thank you!
 
No problem,

I thought I would reply with some additions. My colleague informed me that you can get localized buckling after the beam has deformed. Localized buckling means that it can kink at the edges.
 
I see. That does make sense. Would that lead to structural failure though?
 
I honestly don't know. I would suspect, however, that the failure criterion that you need to worry about is the bending stresses due to the deflection.
 
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