軸対称変位形流体要素による浮屋根式タンクの地震時スロッシング解析

抄録

The floating roofs are widely used to prevent evaporation of content in the large oil storage tanks. The 2003 Tokachi-Oki Earthquake caused severe damage to the floating roofs due to liquid sloshing. This accident becomes a cause and the structural integrity of the floating roofs for the sloshing has been actively studied. This paper presents the axisymmetric finite element analysis for the sloshing response of floating roofs in cylindrical storage tanks. The hydrodynamic coupling of fluid and floating roof under seismic excitation is taken into consideration in the analysis. It is assumed that the fluid is compressive and inviscid, and the roof is linear elastic while the sidewall and the bottom are rigid. The fluid behavior is formulated in terms of displacement as the Lagrangian approach. In order to remove the spurious modes, the free vibration analysis is carried out. The highly precise response solutions are given if the effective modes are only taken into consideration in the modal composition.