A Study on Combination of Two Friction Dampers to Control Stayed-Cable Vibration Under Considering its Bending Stiffness

Abstract

The stayed-cable is one of vital component of cable-stayed bridges. Stayed-cable is often very long with a small diameter and low mass, which can be considered horizontal flexible structure with very low natural frequency. Under the influence of cyclic load in specific conditions, stayed-cable can store the energy and vibrate with large amplitude. This paper focuses on studying the methods of two-friction damper combination for reducing the cable vibration, and evaluates the capacity of friction-damper parameters in mitigating the vibration of stayed-cable. The results show the relationship between the damping factor of stayed-cable and various parameters such as Equivalent viscous constants, friction, spring constant, points attached damper to stayed-cable. For long-span cable-stayed bridges, cable has relatively large diameter and it is normally covered by grouting mortar or Epoxy. Consequently, its bending stiff-ness is considerably increased. Therefore, it is necessary to take into account its bending stiffness during the vibration analysis process. From these results, designers can assess and choose the attaching point as well as parameters of friction damper, which are optimal for specific stayed-cable.