Modal analysis ANSYS-Simply supported beam

[Xtina]

Hi all, i am performing a modal analysis of a beam in ANSYS. In the laboratory, the beam is supported on transversal steel bars, so vertical positive displacements are allowed, and the bars are fixed to the ground. I tried with contact surfaces between the beam and the steel bars with standard behavior, because the typical rigid supports constrains too much the displacements. The problem comes in the results of the modal analysis, the frequencies that I obtain belong to the set beam-steel bars? What could I do to get the beam frequencies? Is it possible to assume that the beam's behavior is more likely to a free-free condition than a simply supported (UX=UY=UZ=0) condition since there is a loss of contact between the beam and the bars? I will be grateful for any suggestion.

Thanks in advance.