Vibration Control of MDOF Structural System using Tuned Liquid Damper

Abstract

A Tuned Liquid Damper belongs to the passive vibration control device family installed on the top of the structure which dissipates the external excitation energy through liquid sloshing. In order to design an efficient TLD, knowing optimum TLD parameters and liquid behaviour is of crucial importance. The main advantage of TLD when compared to other form of dampers is that they can be easily designed and implemented with low installation and maintenance cost. This study investigated the structure response when coupled with and without TLD under sinusoidal excitations. For our simplicity we can relate any multidegree of freedom framework to single level of degree framework by making out an identical equivalent structure of any given structure.

With the consideration of presence of properly designed TLD on structure for controlling the structural vibration, a markable decrement of about 45-55 percent in vibrations is observed for siusoidal floor load case thereby proving the effectiveness and efficiency of TLD in dampening vibrations. In this study the exactness of the current models which can correctly depict the fluid movement conduct is researched and is contrasted with other present model for sinusoidal floor load ,sinusoidal ground movement and earthquake ground motion case for different frequency content range depending upon Ap/Vp ratio categorised as High Frequency Content for PGA/PGV >1.2, Intermediate Frequency Content for 0.8<PGA/PGV<1.2 and Low frequency content for PGA/PGV<0.8.A parametric study of 15 different earthquakes for differernt mass ratio proposes that the mass ratio of 0.05 is most effective in reducing the structural response for high and intermediate frequency content earthquakes and for low frequency content earthquakes mass ratio of 0.02-0.05 is found out to be most effective.