Optimization of tuned liquid dampers for controlling theearthquake response of buildings

The Tuned Liquid Damper (TLD) is a rigid tank containing liquid and positioned on one floor of a building with the aim of reducing the dynamic response of the structure to external excitations. The basic idea behind the use of TLD is that the sloshing natural frequency of the liquid is tuned with the fundamental natural frequency of the building so that its dynamic response is reduced. The mathematical model of the TLD is derived by taking advantage of a number of studies performed in the aerospace field to determine the effects of oscillations of the fuel into tanks of aerospace vehicles. The mathematical model can be used to determine the natural frequency for sloshing of the liquid as well as the capability of the liquid to dissipate energy as a function of the geometric properties of the tank, i.e. its diameter and the liquid level. The objective of this work is to integrate knowledge from both the structural and the aerospace fields and address the problem of determining the optimal properties of the tank in order to reduce the vibrations of the building. The optimization task is performed by using advanced techniques such as Genetic Algorithms.