Free vibration of laminated circular piezoelectric plates and discs

The free vibration characteristics of laminated circular piezoelectric plates and discs are considered using a discrete-layer model of the weak form of the equations of periodic motion. Through-thickness approximations are used for the three displacement components and the electrostatic potential, resulting in an accurate representation of the discontinuity in gradients of these quantities from the mismatch in material properties at a dissimilar interface. In the radial and circumferential co-ordinates, several different approximation functions are used that depend upon the type of problem being considered, specifically the boundary conditions at the outer edge of the solid. Representative cases are studied both for thin plates and for thick discs. Excellent agreement is found with results of previous studies, and several new results are presented. (C) 2000 Academic Press.