Weird buckling behaviour with multiple Load Cases?

Dear experts,

I´ve observed a weird behaviour related to the Buckling Factors of some lattice mast, but I may be doing something completely wrong as well :slight_smile:

In BuckNII.gh (586.9 KB), there is a huge difference in the lowest BF obtained directly from the worst normal forces NII (around 0.75) and all the BFs obtained from the NII forces computed for each one of the 23 Load Cases separately (BFs over 20).

As far as I know, the strongest NII forces among all Load Cases (LCs) are computed by AnalyzeThII and then used by BModes to obtain the requested BFs.

Then, how is it possible that a structure that is supposed to buckle using the worst NII forces (BF < 1) does not buckle (BF +20 >> 1) when each LC is analysed individually?

Thank you very much for your help!

PS: This question would be related to a previous topic I initiated some time ago:

Dear @Vigardo,
I could not open your definition sine the model did not de-serialize. Could you send the model or possibly a simplified version of it? It would be very interesting to see what causes the surprising result.
Did you take a look at the NII-values after ‘AnalyzeThII’ via the ModelView-component and the buckling shape?
–Clemens