Abstract
In the aseismic design of liquid storage tanks an assumption that the tank wall is a rigid body has conventionally been made. However, since the size of liquid storage tanks becomes larger, the dynamic rigidity comparatively decreases and it is necessary to include deformations of the tank walls in the design of tanks. In this study, a numerical method was developed for Axi-Symmetric analysis of tank structures including hydrodynamic and foundation interaction effects. The finite element method was newly developed for the internal liquid based on the velocity potential theory. In order to absorb the radiation wave energy through the boundary, a viscous boundary has been employed. Validity and utility of the program are demonstrated by some test calculations including those for a tank made of concrete.