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Problems with frequency response analysis

Problems with frequency response analysis

Problems with frequency response analysis

(OP)
Hi,

 

I'm doing a frequency response analysis on a cantilevered beam.  I'm interested in the moments along the length of the beam when it is being forced at its natural frequency.  I've modelled it with beam elements and performed a modal analysis initially, with all the output file options checked.  I'm then doing a frequency response analysis... I've set up the damping, force amplitude, and frequency tabs as instructed in the truss tower tutorial (but with the correct values for my simulation obviously) and the simulation runs fine and gives me results (with as many load cases as there were results from the modal analysis).  However, the frequency at which the results occur is not given, saying "not available".  

I've attached a zip of the model.

The simulation design scenario is what 'should' happen when the model is excited at it's first natural frequency.  The frequency response scenario is the same in every way, but even if I manually type in the natural frequency the mode shape is completely different to what I would expect from the modal analysis and MES simulation.

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