A Study on Refined Analytical Method for Free Vibration Analysis of Laminated Composite Cylindrical Shells Using Equivalent Curvatures

In this report, refined analytical method is proposed for calculation of natural frequencies of laminated composite cylindrical shells. Proposed computational model is based on the method which estimate rotation of transverse cross section and the curvature of middle-plane of laminated shells introducing equivalent transverse shear stiffness and equivalent curvature. The method includes transverse shear deformation and material anisotropy of composite materials. Natural frequencies calculated in numerical examples for graphite/epoxy cross-ply laminated composite cylindrical shells simply supported at both ends are compared with the solutions by the first-order shear deformation theory (FSDT) and classical shell theory (CST). Results obtained by the present method are in good agreement with results by FSDT as about several percent errors for in spite of thick and shorter cylindrical shells.