Hello all

I am trying to model the resonant periods of a 2-dimensional dam on Solidworks.

For the method I need to use, two different scenarios are required (See pictures attached)

1: Base of the dam is modelled as rigid

2: Dam "attached" to elastic foundation

The first scenario gives a resonant period for mode shape 1 of 0.41278 seconds, which is in the expected range. However, the second scenario gives a period of 38.07 seconds, which is not in the expected range (It should definitely be less than 1 second). I am not very experienced with the frequency package, nor necessarily the mathematics behind it all, but I am guessing that the massive increase has something to do with the added system in the analysis, and therefore does not give the period of the dam alone. Is there any way to isolate the dam in the analysis to get the resonant period of the structure alone?

Regards

Dario