Numerical and experimental assessment of tuned liquid dampers efficiency for structural response reduction of tall buildings under earthquake excitation

The behavior of tuned liquid dampers subjected to random base motion has been investigated extensively. However, their efficiency in reducing the dynamic response of structures under earthquake excitation is still not completely understood. A non-linear modeling strategy based on Yu’s model was implemented to perform numerical analyses on a 21-story building subjected to seismic base excitation. Three tank shapes were investigated: a rectangular tank, a vertical cylindrical tank, and a horizontal cylindrical innovative TLD. An experimental campaign has been conducted on a scaled physical model in order to calibrate the numerical model and validate its results. The effects of the dampers were evaluated in terms of structural relative displacements and absolute accelerations. Dampers efficiency in reducing the structural response was evaluated for different mass ratios. The non-linear numerical model showed good capability in reproducing experimental results for the rectangular tank. Some limitation has been evidenced for the other tank shapes, suggesting the use of different numerical techniques or the development of specific non-linear mechanical models. Results obtained from experimental and numerical analyses show that reduction of peak response during earthquake excitation is often limited and dependent on ground motion history. However, TLDs where found to be effective in reducing structural response when the structure experience free vibration motion.