A recently developed hybrid mass damper (HMD) system and its application to
a 36-storey high-rise building with a bi-axial eccentricity, located in To
kyo, are presented. This new HMD system utilizes a gear-type pendulum and a
linear actuator. Here, the gear-type pendulum is employed to make the natu
ral period of the auxiliary mass comparatively long while minimizing the he
ight of the device, and the linear actuator, on the other hand, ensures smo
oth and noiseless operation of the system. There are several special featur
es in the control method as well; two HMD systems are applied to control th
e transverse-torsional coupled vibration of the building, and also variable
gain feedback (VGF) control technique has been developed to fully utilize
the capacity of the HMD system from weaker to stronger external excitations
.
Free vibration tests as well as control of wind vibrations of the building
induced by the Typhoon 9810 in 1998 were used to verify the performance of
the control system. It was found that the maximum and the root-mean-square
acceleration responses of the building were reduced to 63 per cent and 47 p
er cent of the corresponding uncontrolled accelerations. Finally, the contr
ol performance of the system was confirmed. Copyright (C) 2001 John Wiley &
Sons, Ltd.