Study on Vibration Analysis for Laminated Composite Pipings

A simplified FEM vibration analysis program is developed for laminated composite cylindrical beam structures. In this program, a composite cylinder which has various diameters and thicknesses laminated in various fiber orientations is modeled by a single beam element to decrease the degree of freedom of the vibration problems. Therefore, eigenvalues and transfer functions of laminated composite cylinders can be analyzed without influence from the aspect ratio of the element. In the transfer function analysis, a proportional viscous damping is assumed and a method of surmising theoretical damping is utilized. Using this program, the eigenvalue and the transfer function of CFRP golf club shafts are analyzed. And compared with the experimental results obtained by the impact test. As a result, the validity of this program is proven because the analytical results show good agreement with the experimental ones.