Vibrations of composite plates with intermediate line supports

Abstract

Free vibrations of rectangular composite plates with arbitrary support conditions along the edges and an arbitrary number of intermediate line supports are investigated using the Rayleigh-Ritz method. A procedure is presented for generating polynomial approximation functions that satisfy the essential boundary conditions and zero displacement constraints along each line support, and the stiffness and mass matrix coefficients are obtained by exact integration. Plates that are continuous over many supports are analyzed and the effects lay-up and material properties are investigated. An exact solution is found for predicting some of the vibration modes of plates with simple supports along the edges and equal length spans in each direction. In this case, the fundamental natural frequency is always predicted exactly, and simple results are obtained for finding which lay-up maximizes the natural frequency of the plate.