Numerical Analysis of Base Isolated Liquid Storage Tanks

Abstract

Liquid storage tanks behave in a different manner as compared to any other type of structure when subjected to a dynamic loading, wherein the motions of lower and upper liquid are non-identical in nature. The upper liquid mass is named convective mass, which is responsible for sloshing and subsequent damage to the tank. Base isolation is an effective method in seismic response reduction of structures. Laminated rubber bearings (LRB) and lead core rubber bearings (LCRB) are used as effective base isolators for seismic response reduction across the globe. The current study deals with the reduction of hydrodynamic pressures induced due to seismic action in square and rectangular flexible tanks when isolated with LRB and LCRB. The transient analysis of 3D ground supported base isolated tanks subjected to El Centro and Northridge ground motions is performed using FE software. The coupled acoustic structural approach is employed in order to incorporate the fluid–structure-interaction effects. Variation of convective displacement is assumed according to a linear wave theory. It is found that a considerable reduction in impulsive pressures and sloshing is achieved by employing a lead core rubber bearing system. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.