Nonlinear sloshing response of liquid-filled rectangular concrete tanks under seismic excitation

The current study is mainly focused on nonlinear sloshing analysis of rectangular liquid storage tanks. The main response quantity of interest is free surface sloshing height. There are some key factors to be investigated in order to make a better understanding of the performance of liquid tanks under seismic loading. These include three-dimensional geometry, corner sloshing, tank aspect ratio, bidirectional loading, and earthquake frequency content. The main focus of this work is to investigate these important parameters through a comprehensive parametric study using a rigorous finite element technique capable of accounting for nonlinear fluid-structure interaction effects. The validity of current code provisions in seismic analysis of such structures is then investigated by comparing the obtained numerical results with those recommended by current practice and important conclusions are drawn. The present paper suggests that the sloshing nonlinearity could have a significant effect on the seismic performance of liquid containing structures and failing to account for it properly could introduce a major concern with respect to their satisfactory performance for a certain group of tanks in particular shallow tanks.