NUMERICAL SIMULATION OF VIBRATION OF NON-HOMOGENEOUS PLATES OF VARIABLE THICKNESS

Abstract

Differential Quadrature Method (DQM) is used to analyse free transverse vibrations of non-homogeneous orthotropic rectangular plates of variable thickness. A new model to represent the non-homogeneity of the plate material has been taken which incorporates earlier models. Following Lévy approach i.e the two parallel edges are simply supported, the fourthorder differential equation governing the motion of such plates of variable thickness has been solved for different combinations of clamped, simply-supported and free-edge boundary conditions. Effect of non- homogeneity together with other plate parameters such as orthotropy, aspect ratio and foundation modulus on the natural frequencies has been studied for the first three modes of vibration. Numerical results are presented to illustrate the method and demonstrate its efficiency. Normalized displacements are presented for specified plates for all the three boundary conditions.

Keywords

• DQM, orthotropy, variable thickness, non-homogeneity, elastic foundation.

References

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