OICC Press Journal of Solid Mechanics 2008-7683 1 1 2009 04 30 Comparison of Various Shell Theories for Vibrating Functionally Graded Cylindrical Shells 73 83 EN M Javadinejad Department of Mechanical Engineering, Islamic Azad University, Khomeinishahr Branch Journal Article 2009 04 30 The classical shell theory, first-order shear deformation theory, and third-order shear deformation theory are employed to study the natural frequencies of functionally graded cylindrical shells. The governing equations of motion describing the vibration behavior of functionally graded cylindrical shells are derived by Hamilton’s principle. Resulting equations are solved using the Navier-type solution method for a functionally graded cylindrical shell with simply supported edges. The effects of transverse shear deformation, geometric size, and configurations of the constituent materials on the natural frequencies of the shell are investigated. Validity of present formulation was checked by comparing the numerical results with the Love’s shell theory.