Diploma Thesis, July 2010
Seismic actions on a liquid storage tank may cause severe damage. In particular, the occurrence of significant meridional compressive stresses due to the seismic overturning moment can cause buckling, with emphasis on the so-called “elephant’s foot buckling” near the tank shell base. The present thesis is aimed at computing the seismic action in liquid storage tanks of upright cylindrical shape for different liquid heights. Four standards are mainly employed: API 650 (2003) AppendixE, API 650 (2007) AppendixE, EN-1998-4, EN 14015 AnnexG. The differences between the seismic provisions of the above standards are identified. In addition, the seismic action is computed through a finite element model in program ABAQUS. The numerical results are compared with the provisions of the above standards.