Controlling the seismic response of structures under near-field earthquakes with fluid/structure interaction of cylindrical liquid tanks

Abstract

In this paper, the effectiveness of using nonlinear fluid/structure interaction for controlling the seismic response of the structures under near-field earthquake is investigated. For this purpose an SDOF Structure is considered which is equipped with the circular cylindrical liquid tank. Considering its fundamental mode of vibration, the structure is an idealised model of multi-degree of freedom system. Under 72 horizontal near-field earthquake excitations, the dynamic response of this system is examined studying three liquid sloshing modes. The dynamic response is investigated in the neighbourhood of 1:1 resonance between first unsymmetrical sloshing mode and SDOF structural mode. For this matter, most of the pulse-like earthquakes identified by Baker from NGA-West2 database and some other well-known near-field earthquakes have been used as base excitation. The Energy flow from the structural mode to the first unsymmetrical liquid sloshing mode is explored, and the proficiency of the appended liquid tanks in reducing the dynamic response of the structural system under pulse-liked earthquake is shown. The results show appropriate response reduction using the fluid oscillations for the structure subjected to pulse-like excitations.