Free vibration analysis of circular plates with variable thickness by the generalized differential quadrature rule

The generalized differential quadrature rule proposed recently by these aut hors is applied here to the free vibration analyses of solid circular plate s with radially varying thickness and elastic restraints. The thickness can vary radially in any given continuous form, and it varies exponentially an d linearly in this work. Two regularity conditions corresponding to the pla te center are expressed in explicit formulae, since they have been inexactl y or even wrongly expressed in the literature. Such errors are pointed out in the application of the differential quadrature techniques and in the exp ression of the regularity conditions at the plate center. Numerical results are presented for a number of plates, illustrating the versatility and acc uracy of the approach. (C) 2001 Elsevier Science Ltd. All rights reserved.