On the vibration field correlation of randomly excited flat plate structures, I: Theory

A probabilistic treatment of the vibration field generated by the random vibration of flat plate components is proposed herein. This treatment is based on the computation of the frequency-averaged spatial correlation coefficient of the plate normal displacement. This spatial correlation coefficient is derived using an approximate modal representation based on Bolotin's Method of Integral Estimates. Particular attention is paid to the boundary conditions and results are derived for plates with clamped, simply supported, free or guided edges. A general boundary condition which solely depends on the edge stiffness is employed to model the effect of stiffeners on the plate vibration field. Information about the type of excitation is also incorporated in this model. This approximate representation is compared to that obtained by a modal summation method and good agreement between both approaches is obtained for cases in which at least eight modes are resonant in a frequency band. (C) 1998 Academic Press.