FREE-VIBRATIONS OF UNCERTAIN COMPOSITE PLATES VIA STOCHASTIC RAYLEIGH-RITZ APPROACH

The eigenproblem associated with the free vibrations of uncertain comp osite plates is dealt with herein. The elastic moduli of the system, t he stiffness of the Winkler foundation on which the plate rests and th e mass density are considered to be uncertain. Given their random fiel d-based description, a new method is presented for the computation of the second order statistics of the eigenproperties of the laminate. Fo r the sake of clarity, the deterministic version is introduced first a nd its stochastic extension is then presented and deeply analyzed. Num erical studies are also performed to validate the theoretical approach . (C) 1997 Civil-Comp Ltd and Elsevier Science Ltd.