Experimental study of a hybrid TMD and TLD on structure motion reduction

Extensive experiments were made in this study to investigate the effects of TMD (Tuned mass damper), TLD (Tuned liquid damper) and a hybrid TMD&TLD on structure motion control. Different mass ratios of TMD and different liquid depth ratios of TLD were studied, and various TMD&TLD were used to determine the optimal hybrid TMD&TLD system. For a TLD system, the liquid depth ratio (do/L, do = liquid depth, L = tank width) must be smaller than 0.4 to have significant response reduction. Besides, the maximum motion reduction can be obtained when the liquid depth ratio decreases to 0.2 and the motion reduction rate can reach nearly 70%. The maximum motion reduction always occurs when the exciting frequency is equal to the fundamental frequency of the TLD. However, the violent sloshing of liquid in the TLD tank with small liquid depth ratio is found in the experiments. For a TMD system, the TMD mass ratio must be greater than 10% to have a notable response reduction. The addition of TMD to the TLD and base structure system can calm down the violent sloshing of liquid in TLD tank and the hybrid TMD&TLD has the best performance of the structure motion control.