EFFECT OF AN ELASTIC-FOUNDATION ON AXISYMMETRICAL VIBRATIONS OF POLAR ORTHOTROPIC MINDLIN CIRCULAR PLATES

Analysis and numerical results are presented for the axisymmetric vibrations of polar orthotropic circular plates of uniform thickness resting on an elastic foundation, according to Mindlin's shear theory of plates. A Chebyshev collocation technique has been employed to obtain the frequency equations for the transverse motion of such plates, for two different boundary conditions. The effect of the elastic foundation together with the orthotropy on the natural frequencies of vibration is illustrated for different values of thickness of the plate for the first three modes of vibration. Transverse displacements are presented for a specified plate. A comparison of frequencies with the corresponding values obtained from classical plate theory leads to some interesting conclusions.