Free Vibration of Doubly Tapered Laminated Composite Beams using Hierarchical Finite Element Method

Abstract

In the present study, free vibration response of symmetric thickness-and-widthtapered (doubly-tapered) laminated composite beams is considered. Considering a variety of tapered configurations according to different types of ply drop-off configurations, both conventional and hierarchical finite element formulations are developed based on cylindrical bending theory of laminated beam. Natural frequencies of different types of internally-tapered composite beams are determined. Comparison of the hierarchical finite element solution with the Rayleigh-Ritz solution and a higherorder finite element solution is performed. A parametric study is conducted to investigate the effects of boundary conditions, width-taper-ratio, thickness-taper configurations, thickness-tapering angle, laminate configuration and compressive axial force on the free vibration response of doubly-tapered laminated composite beams.