Modeling of deepwater-type rectangular tuned liquid damper with submerged nets

An analytical model for describing the effectiveness of deepwater-type tuned liquid damper (TLD) with submerged nets for suppressing horizontal vibration of structures is proposed. TLD is a damping device for suppressing the vibration of long-period structures such as high-rise buildings, tall towers, the pylons of cable-stayed bridges, and so on. The damping force is created by the hydrodynamic force caused by the sloshing of water contained in rectangular tanks located on top of such structures. In this study, we proposed the dynamical model for analyzing deepwater-type TLD (DTLD) where the liquid depth is deep compared with the length of the rectangular tank. In particular, the effect of hydraulic resistance produced by submerged nets installed in the tank is examined intensively. In the analysis of DTLD, employing finite amplitude wave theory, we obtained the hydrodynamic force and the dissipation energy by using Galerkin method, taking the effect of submerged nets into account. The calculated results thus obtained are compared with experimental results, by which the validity of the modeling methodology is confirmed. Finally, the case in which DTLD with nets is installed on an actual structure is investigated both theoretically and experimentally and the the performance of DTLD is illustrated.