Vibration of Laminate-Faced Sandwich Plate by a New Refined Element

Abstract

An efficient six-noded triangular element based on refined plate theory is developed for the analysis of sandwich plates with stiff laminated face sheets and it is applied to a free vibration problem in this paper. The plate theory represents parabolic through thickness variation of transverse shear stresses with continuity at the layer interfaces, which introduces discontinuity at these interfaces for the shear strains. It is to be noted that the plate theory requires unknowns at the reference plane only. Moreover, it ensures a shear stress-free condition at the top and bottom surfaces of the plate. Thus, the plate theory has all of the features required for an accurate modeling of laminated sandwich plates. The plate theory suffers from a problem in its finite element implementation since it requires