In-plane Vibration Analysis of Symmetric Angle-ply Laminated Composite Arches

The in-plane free vibration analysis of symmetric angle-ply laminated composite arches is carried out by finite elements method. The rotary inertia and shear deformation effects have been included in the analysis. Arches with opening angle (α) from 30° to 270° are taken into consideration. Parametric studies are performed to study the effects of fiber orientation angle, boundary conditions, material orthotropicity, radius-to-width ratio and number of layers on natural frequencies. The validity of the finite element model is shown by comparing the results with those available in the literature. Mode shapes are presented for two different cases. It is found that fundamental in-plane natural frequency of laminated composite arches can be substantially increased by 30 to 60%, by using angle-ply instead of cross-ply. This percent increase offers a considerable advantage that, for arch beams, angle-ply lamination can be preferable to cross-ply lamination.