A study on countermeasures against wind-induced cable vibrations in cable-stayed bridge by changing vibration modes: 4th report, experimental application to an actual cable

In order to suppress vibrations of stay cables in cable-stayed bridges, the authors developed a new vibration reduction method called "Changing vibration modes method" using a permanent magnet. With this method, growth of the unstable fundamental vibration mode is prevented by dissipating energy of higher stable modes. The authors have confirmed in former reports that the proposed method effectively reduces the self induced cable vibrations by both theoretical analyses and wind tunnel tests and design method of the device was proposed. In this report, first, the design process of a prototype of a control device is described. Second, higher mode vibrations generated by the action of the device were confirmed from the results of free vibration tests. Finally, efficiency of the proposed countermeasure against rain wind induced vibrations of an actual cable is clarified.