| 摘要 |
PROBLEM TO BE SOLVED: To effectively and surely control every vibration such as wake galloping, rain vibration, over excitation of a diagonal member cable of a cable stayed bridge. SOLUTION: A damper is set between a main girder 1 of a cable stayed bridge and a diagonal member cable 2 and reduces the vibration of the diagonal member cable 2 with confining/releasing motion by a magnet, it is constituted of a magnetic material 3 mounted to the diagonal member cable 2, an electromagnet 4 provided in an anchor member 6 fixed to the main girder 1 by approaching the magnetic material 3 and a controller 5 for controlling impressed voltage of the electromagnet based on wind velocity, confining force of the diagonal member cable is changed in accordance with wind velocity, and it is made to correspond with vibration of every wind velocity. Or, the diagonal member cable is connected to the main girder with a damper, the magnet capable of absorbing the basic end of a piston rod is provided in the inside of a cylinder of the damper, and the damping effect by both magnet and damper can be provided. |
