Study on vertical load acting on whole roof of cylindrical tanks in nonlinear sloshing including extremely large load

Ikesue, Shunichi*; Morita, Hideyuki*; Sago, Hiromi*; Yokoi, Shinobu*; Yamamoto, Tomohiko  

When a cylindrical tank is excited by seismic waves, the motion of free liquid surface, called sloshing, may occur inside the tank. When the high-amplitude sloshing occurs, the free liquid surface collides with the roof of cylindrical tank, and the impulsive vertical load acts on the roof. In this study, the cause of this extremely large load was discussed by analyzing the CFD analysis result. As a result, it was showed that the previous weak roof collision deformed the liquid surface into a flat shape and the flat liquid surface collided with the roof. The phenomenon caused the extremely large load acting on the roof. From this result, it was clarified that the history of roof collision has a large influence on the vertical load acting on the roof.