Abstract
The present study is discussed about the seismic risk assessment of steel tanks when a strong earthquake excitation develops a plastic deformation of base plate by a rocking motion of the tank.
Current seismic design guidelines underestimate the seismic safety of buckling failure at the side wall, because the stiffness degradation of the tank is overestimated with the structural characteristic factor Ds.
The present study proposes the exact estimation approach of the seismic safety of elephant foot buckling failure at the side wall as well as the crack failure of the base plate. The seismic performance of the tank is also developed on the limit state design method to provide the fragility curves for the damage modes of the side wall and base plates.
