Seismic response of thin shell storage tanks

A finite element formulation is described, for the numerical and computational modelling of tanks with and without sloshing of contained liquid. The tank wall and roof are modelled with isoparametric elements, ring stiffeners are modelled with Timoshenko beam elements, and the contained liquid is represented by degenerated solid elements constituting a practical means of addressing fluid-structure interaction. For complete generality, shear-locking effects are eliminated. To exemplify its applicability, the seismic analysis of the response of a typical tank is presented, for a given time-record of a synthetic earthquake. Some natural frequencies and mode shapes of the complete structure are given, as well as instantaneous deformed shapes and envelopes of shell stress resultants.