Effect of Rotational Restraint at Damper Location on Damping of a Taut Cable with a Viscous Damper

Abstract

The installation of an external damper on a cable of a cable-supported bridge is often associated with attachments or support devices that trigger vibration restraints at the damper location. This paper investigates the effect of rotational restraint at the damper location on additional damping of a taut cable with an installed viscous damper. An asymptotic solution is employed to derive the asymptotic form of cable complex eigenfrequencies and its damping ratio, in which the flexural rigidity of the cable and those damper restraints including rotational stiffness, damper stiffness, and support stiffness are taken into account. The investigation by a numerical example indicates that by considering rotational restraint, the additional damping of a cable is always lower than its values in the case of no rotational restraint.