Dynamic Behavior of Base-Isolated Flexible Rectangular Fluid Containers

An analytical method is proposed to determine the dynamic response of 3-D base isolated rectangular fluid containers with four flexible walls, subjected to seismic ground motion. By applying Rayleigh-Ritz method using the vibration modes of flexible plates, fluid-structure interaction effects on the dynamic responses of fluid containers are considered. A mechanical model, which takes into account the deformability of the tank wall, is developed. The maximum seismic loading of the base at the tank and a section immediately above it can be predicted by this model. Accordingly, a 2-D simplified model is proposed to evaluate pressure distribution on the flexible tank wall. The effects of base-isolation on theseismic response of rectangular liquid storage tanks subjected to horizontal seismic ground motion are presented. Results show that seismic base isolation can be an efficient way to reduce dynamic responses such as base shear, base moment and hydrodynamic pressure

Keywords:

Rectangular tank , Fluid-structure interaction , Seismic design , Rayleigh-Ritz method , Base-isolation