Study On Seismic Response Control Of Tall Buildings Using The System Of Controllable Tuned Liquid Damper

Structural control is a new field for wind resistant and earthquake resistant design of buildings. Controllable tuned liquid damper (TLD) as a semi-active control device has been proposed recently. The system of controllable tuned liquid damper requires a small power source to operate and utilizes the response of structure to develop the control force by the motion of fluid in the device that is regulated by algorithm using the measured response. Controllable TLD can enhance its applications over a wider frequency band than passive TLD.A new model of controllable TLD using a rectangular tank with vertical baffles is presented firstly in the paper. Compared with the old type model of controllable TLD, the control system using new model is easily implemented and analyzed with theories. The main purpose of the study is to investigate the feasibility of the control system using new model for reducing the multi-modal responses of tall buildings, and to verify the effectiveness of seismic response control with the control system.As a primary study on the new model, linear water wave theory is utilized to study liquid sloshing in a rectangular tank with vertical baffles. The results help us to know the basic behavior of the new model. Then from Navier-Stokes equations, volume of fluid (VOF) method is applied to simulate dynamic response of controllable TLD. Volume of fluid method not only can be used to study liquid sloshing in controllable TLD as the baffles fixed, but also can be used to study the dynamic characteristics as the baffles moving. It is indicated that liquid viscosity and non-linearity of fluid motion should be considered for new model of controllable TLD under large amplitude excitation even for deep water, and the assumption based on small amplitude excitation is not suitable. When the baffles in the tank are fully open or fully closed, large sloshing force that can be produced as excitation frequencies approximate the natural frequency of corresponding status of the model.To investigate the action between controllable TLD system and tall buildings, the motion equations for controlled structure with controllable TLD system subjected to earthquake excitations are built up. As the system of controllable TLD relates to...