磁流变阻尼器控制拉索振动的优化参数研究

Optimal parameter study for control cable vibration using magnetorheological damper

采用磁流变阻尼器控制斜拉桥拉索振动是一项新的拉索减振技术.根据不同拉索的几何、力学条件确定磁流变阻尼器的优化电压是取得最佳减振效果的关键.基于组合磁流变阻尼器的拉索运动方程,采用改进的Bouc Wen磁流变阻尼器模型,对安装磁流变阻尼器后多根拉索的阻尼特性进行了数值仿真计算,得到了拉索系统模态阻尼比与阻尼器输入电压的关系.采用非线性最小二乘方法,得到了考虑拉索参数、振幅、模态阶次及阻尼器安装高度等因素的阻尼器优化设计曲线.并在岳阳洞庭湖大桥进行了实桥振动控制试验,结果与数值仿真具有很好的一致性.图9,表1,参8.

Control cable vibration using magnetorheological(MR) damper is one of the newest techniques in the domain. Based on the motion differential equation of cable system incorporated MR damper and proposal BoucWen MR damper model, numerical simulations are conducted on six cables with different size and load to investigate dynamic characteristic of cable system. Relationships of first three modal damping ratio of cable versus voltage input to MR dampers are acquired. With nonlinear leastsquare fitting program, optimal voltage design curve counting these factors, such as cable parameters, vibration amplitude, modal, attachment highness of damper, is obtained. Field tests to confirm simulation results are implemented on the Dongting Lake Bridge. Test results are consistent with analytical one. 9figs.,1tab.,8refs.