Performance Test of Secondary Mass Dampers for Vibration Control of Tall Buildings

For a secondary mass damper such as tuned liquid damper (TLD) or tuned liquid column damper (TLCD), whose moving mass is liquid, it is impossible to pre-fabricate the damper in a factory for the identification of dynamic properties. Also, it is not easy to pre-fabricate a concrete tuned mass damper (TMD) in a factory whose moving mass is made of concrete. In this paper, an identification method of dynamic properties of secondary mass dampers based on the forced vibration test is presented. Decoupled equations of motion are derived from a coupled equation of motion of building and damper. The decoupled equations of motion are then applied to the system identification using the response of the damper as an input and the response of the building as an output. The proposed method is applied to numerical examples and an actual TMD and TLCD installed in buildings.