解析解と有限要素法の結合解法による浮屋根式円筒液体貯槽の非線形スロッシング解析

抄録

A hybrid analytical and finite element method is proposed to solve the nonlinear sloshing problem in a floating-roof type cylindrical liquid storage tank under long-period ground motion. The contained liquid is assumed to be inviscid and incompressible and the flow is assumed to be irrotational, while the floating roof is considered as a Kirchhoff plate undergoing large deflection. The proposed method is based on representation of the liquid motion by the analytical solution to the potential theory that satisfies the rigid wall and bottom conditions. This requires only the discretization of the liquid surface and the floating roof into finite elements, thus leading to a computationally very efficient method compared with full numerical analysis. Numerical examples are presented to investigate the nonlinear sloshing in oil storage tanks with single-deck type floating roofs damaged during the 2003 Tokachioki earthquake.