Study On Structural Vibration Control Of Liquid Column Vibration Absorber

The current trend toward structures of increasing heights and the use of light-weight, high strength materials and advanced construction techniques has led to more flexible and lightly damped structures. Therefore, the structures are very sensitive to environmental excitations such as wind, ocean waves and earthquakes, leading to vibrations inducing possible structural failure, occupant discomfort, and malfunction of elevators and equipment. Hence, it has made it critical to search for practical and effective devices to suppress these vibrations.The most commonly used passive devices are the tuned mass damper (TMD) and the tuned liquid damper (TLD). TLD is a special class of TMD where the mass is replaced by liquid (usually water). The tuned liquid column damper (TLCD) is a special type of TLD that rely on the motion of a liquid column in U-tube-like container to counteract the forces acting on the structure, with damping introduced through a valve or orifice in the liquid passage. TLCD is a type of effective device of passive vibration control. Up to now, the investigations on TLCD mainly concentrated on constant cross section U-tubes. There have been great advances in structural vibration control under long period excitation with TLCD, but the studies of structural vibration control under relative short period excitation need to be developed. The reason is the natural period of TLCD is only related to the length of the liquid column. So the range of the natural frequency is very narrow.Considering the defects of the TLCD, in this paper, the dynamical characteristics of liquid column vibration absorber (LCVA) will be studied. The cross-section of the LCVA is variable. The range of the natural frequency is wider when changing the section of U-tubes. In this paper, the theoretical investigation of the SDOF and MDOF structural systems with LCVA is presented firstly. And the comparison of the structures with and without LCVA will be developed. Moreover the basic parameters of LCVA will be optimized. Secondly, a 4-story steel structure model with LCVA under the base motion will be used to conduct experiment in order to verify the conclusion of theoretical investigation. Finally, through dynamical responses of a high building with LCVA under wind excitation in a numerical simulation way, the energy dissipation effect will be presented.