宁夏永宁黄河公路大桥斜拉索减振方案研究

Study on Vibration Reduction Scheme on Stay Cables of the Yongning Yellow River Highway Bridge in Ningxia

斜拉索是斜拉桥的主要受力构件,但极易受风致振动及内参数振动,影响整桥的使用寿命。本文以宁夏永宁黄河公路大桥为背景,提出采用拉索外置阻尼器、气动措施并用的综合减振方法来控制其振动,经分析采用具有半主动控制的永磁调节式磁流变阻尼器来增加附件阻尼,提高拉索振动对数衰减率,有效减小拉索在3 Hz以下的大幅振动,确保桥梁安全运营。

The stay cable is the main component of the cable-stayed bridge, but it is easy to be affected by the wind-in- duced vibration and the internal parameter vibration, which affects the service life of the whole bridge. Based on the back- ground of the Yongning Yellow River highway bridge in Ningxia, the paper put forward a comprehensive method using vibra- tion damper, cable external aerodynamic measures to control the vibration. The permanent magnet with semi-active control adjustable magnetorheological damper was adopted to increase the damping of cable vibration accessories, so as to improve the rate of decay, effectively reduce the vibration of cables below 3 Hz, it could ensure safe operation of bridge.