Natural Frequencies Calculation of Composite Annular Circular Plates with Variable Thickness Using the Spline Method

The present study adds to the knowledge of free vibration antisymmetric angle-ply annular circular plates with variable thickness for simply supported boundary conditions. differential equations in terms displacement and rotational functions are approximated using cubic spline approximation. A generalized eigenvalue problem is obtained solved numerically an eigenfrequency parameter associated eigenvector coefficients. examined circumferential node number, radii ratio, different variations, number layers, stacking sequences lamination materials.