A dynamic analysis of cable vibration control on cable-stayed bridges

Abstract

Long-span cable-stayed bridge design requires special attention to address the dynamic effects of wind loading. The main cables of large cable-stayed bridges often incorporate transverse wires connected to the stay cables. This ideology takes advantage of the fact that the differing length-adjacent stay cables have varying resonant frequencies. Vibrations induced from wind and other live loading conditions can be detrimental to cabled structures. Long-span cable-stayed structures are particularly vulnerable to this phenomenon, as evident on a number of structures constructed recently throughout the world. A tremendous amount of energy can be stored in long cables as they oscillate in their fundamental mode. To mitigate these effects, strategies such as stringing light cables between the planes of the main cables connecting them together and eventually to the deck, adding mass or viscous dampers to the cabling system are employed. Factors influencing the vibration of cables include length, dead load tensile forces, section modulus, and load conditions. Designs of long-span cable-stayed structures must incorporate strategies to alleviate cable vibrations. Therefore, the motivation for this research belongs to analytically review the effectiveness of altering the fundamental frequencies of cabling systems on cable-stayed structure.