Movable anchorage system with FPB for vibration control of stay cables

Wind or rain-wind induced vibrations of stay-cables can be detrimental to the health of cable-stayed bridges. Externally attached dampers have been successful used for the mitigation of the vibration of relatively short stay-cables. For long stay-cables, however, such damper systems cease to be effective as dampers can only be attached in the proximity of the bridge deck for aesthetic or practical reasons. This paper investigates a movable anchorage system with a Friction Pendulum Bearing (FPB) device. An analytical model of the cable-damper system is developed based on the taut string representation of the cable. The performance of the proposed system is assessed through a series of analysis of the cable vibration due to a Gaussian white noise excitation. A case study with realistic geometrical parameters is also presented to establish the validity of the proposed system. The proposed system is found to significantly reduce the response of the cable as compared to the conventional external damper system, thus demonstrating its potential as a viable alternative for the mitigation of rain-wind induced vibrations of long stay cables.