Damping of Stay Cables by Semi-Active Friction Dampers

Abstract

<p>This paper concerns experimental investigations of passive and semi-active friction dampers for stay cables. Different control strategies have been tested and the damper performances have been compared. The present experimental results with the semi-active device show that it is possible to outperform the passive damping by a factor of 1.8 on the obtained damping ratio with the same maximum damper force. This has been achieved by using two key concepts in the control strategy for the semi-active damper. The first concept is real-time adaption of the damper force to the corresponding vibration amplitude of the cable and the second concept is realization of apparent negative stiffness by real-time on-off control of the friction damper brakes.</p>