Seismic analysis of base-isolated liquid storage tanks on the layered ground

In this study, a base-isolated liquid storage tank subjected to seismic ground motion is numerically simulated on frequency domain considering three-dimensional liquid-structure-soil interaction. A hybrid formulation, which combines the versatility of finite elements for tank structure and the efficiency of boundary elements for liquid and soil region, is adopted for efficient modeling. The base-isolation system using the effective stiffness and damping ratio is also included in the formulation. In order to demonstrate the accuracy and validity of the developed solution, the numerical results are compared with the reference solutions in each interaction problem. The effects of the liquid filling ratio and the stiffness of base-isolation system on the behavior of the liquid storage tanks are analyzed.