Vibration Control of Hakucho Bridge Tower under Construction Using Actively-Controlled Mass Damper

Abstract

Free-standing bridge towers, in general, suffer from vibrations caused by wind. In order to reduce vibrations, an actively-controlled mass damper was applied to Hakucho Bridge tower. In controlling vibrations, the node of the 2nd mode was selected as a settling point of sensors in order to maintain stability for higher order modes of vibration than that to be controlled. The damper was tested to verify damping performance by free vibration and measurement of vibrations caused by wind. High performance has been obtained from results of tests and the effectiveness of this method has been demonstrated.

Vibration Control for Bridge Towers and Field Measurement

“…Active dampers as shown in Fig. 9.10 were installed at the center of the upper middle horizontal strut to reduce the tower top acceleration level down to 0.1 m/s 2 or less, which required the additional damping of 0.18 [8].…”