Reply To: Harmonic analysis and resonance

[dlooman]

1. The usual way is to compare the stress of the resonant response to yield or some allowable stress per code.
2. Clustering does work if damping has been specified.  Clustering should be used so that you get a solution at each natural frequency.  The resonant response will be inversely proportional to the damping value so it's a critical input quantity.  2% is a typical value for welded structures.