A study on multiple tuned liquid column ball dampers (MTLCBDs)

Tuned liquid column ball dampers (TLCBDs) are a relatively new type of liquid dampers in which the motions of liquid in a U-shaped tube counteracts the forces acting on the structure. Damping in the oscillating liquid is introduced through a steel ball rolling by the liquid passage. The tube and steel ball in a single TLCBD-system may acquire enormously large dimensions. One way to decrease the size, and perhaps the total costs, is to replace a single-TLCBD with a multiple (M)-TLCBDs of smaller dimensions. Current literature lacks to address the governing equations of an M-TLCBD and its application in wind response mitigation of tall buildings. In this paper, the governing equations of motion for an MTLCBD-system has been developed. Next, the dynamic response of a tall building, equipped with various MTLCBDs, to harmonic wind excitations is investigated. The influence of different design parameters such as mass ratio, length ratio, and the number of individual dampers on the response mitigation efficiency of MTLCBDs has been studied. Overall, the performance of a MTLCBD is found to be sensitive to the variations in the design parameters mentioned above.