Abstract
The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Seven single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery in Tomakomai, Japan. The pontoons of the floating roofs might be buckled due to bending load during the sloshing. The initial geometrical imperfection may diminish the buckling load of the pontoon. This paper presents the lower bound buckling load of the pontoons based on the reduced stiffness method proposed by Croll and Yamada. The axisymmetric shell finite element method is used in the linear elastic bifurcation buckling analysis.
