Vibration Analysis of Non-Homogeneous Orthotropic Rectangular Plates of Variable Thickness Resting on Winkler Foundation

Differential Quadrature Method (DQM) has been used to analyse free vibration of non-homogeneous orthotropic rectangular plates of parabolically varying thickness resting on Winkler-type elastic foundation. The behaviour of non-homogeneity has been assumed due to exponential variation in Young's modulii and density in one direction. Three different combinations of clamped, simply supported and free edge conditions have been considered. Plots are given to show the effect of foundation parameter together with aspect ratio, taper constant, non-homogeneity parameter and density parameter on the natural frequencies for first three modes of vibration. Mode shapes have been computed for different values of plate parameters. A comparison of our results with those available in literature shows good agreement.