Maximizing the Fundamental Frequency of Laminated Composite Plates with Optimally Shaped Curvilinear Fibers

Abstract

A new design method is proposed here to maximize the fundamental frequency of laminated composite plates reinforced by curvilinear fibers. Spline functions represent arbitrarily shaped fibers and Ritz solutions generate frequency equations. The optimum curvilinear shapes are searched for the maximum fundamental frequencies using genetic algorithms, and the increments of data points which define the spline shape are used as design variables under the limited range of undulation. Comparison of the present analysis method gives good agreement with the finite element method in terms of natural frequencies and vibration modes, and the optimized results show that the present plate with optimally shaped curvilinear fibers gives higher or equal fundamental frequencies than those of the conventional plate with optimally oriented parallel fibers.