Abstract
This paper presents theoretical analysis for free vibration of liquid storage circular cylindrical tanks stiffened by Fiber Reinforced Plastic (FRP) Composites. In this study the tank is modeled by a laminated, circular cylindrical thin shell composed with steel and FRP materials. The equations of motions of the shell are formulated by using the Classical Lamination Theory. Liquid in the shell is assumed to be ideal fluid without rotational motion, and thus the velocity potential function can be introduced to formulate the motion and pressure of the liquid. Frequency equation is derived by using modified Galerkin's method after introducing series form solutions for deformation of the shell and obtaining exact solutions for liquid. Finally, natural frequencies are calculated numerically for the tanks with different dimensions and fiber angles, and then optimum design for the angles are also discussed from the numerical results obtained.
