Analytical and experimental investigations of Modified Tuned Liquid Dampers (MTLDs)

Modified Tuned Liquid Dampers (MTLDs) are a variation of a traditional Tuned Liquid Damper (TLD) which utilize a rotational spring system at the base, and therefore experience combined horizontal and rotational motions as the structure sways. To date, there have been very few studies conducted on MTLDs with experimental validation. In this research study, an MTLD-structure system is investigated using Lu's analytical model. Using Real-Time Hybrid Simulation (RTHS), a state-of-the-art testing method, the capabilities of the analytical model are experimentally verified. Important MTLD parameters such as the dimensionless rotational stiffness parameter, frequency ratio, and damping ratio are studied in detail. RTHS is used to study the effectiveness of the MTLD in mitigating structural response under sinusoidal inputs, as well as a range of ground motion records. It is shown both analytically and experimentally that when properly designed, the MTLD can exhibit more efficiency than a traditional TLD in mitigating vibrations.