Sometimes I obtain negative critical load factors in RF-STABILITY. How do I go about this?
If you obtain negative critical load factors in the module, increase the number of the eigenvalues (eigenvectors) to be determined. If there are not enough eigenvalues, it is not possible to hide the negative eigenvalues and thus show only positive, realistic results.
For these eigenvalues, no stability failure occurs due to tension forces and no conclusion can be made about the buckling behavior of the model.
Alternatively, you can use the ICG iteration to exclude negative critical buckling factor.