针对应用磁流变阻尼器控制斜拉桥拉索振动中参数优化这一关键问题,通过试验研究,建立了目前常用的RD-1005型磁流变阻尼器非线性双黏性模型,得到了基于输入电压、激振频率、振动幅值等参数的磁流变阻尼器等效黏性阻尼系数计算公式;然后提出了考虑拉索垂度、弯曲刚度和倾角等因素影响的黏性阻尼器拉索减振设计方法,修正了Pacheco的设计曲线;最后提出了磁流变阻尼器拉索减振的优化设计方法,并通过实桥试验得到验证。
The method of parametric optimization is investigated for mitigating cable vibration by using magnetorheological (MR) dampers on cable-stayed bridges. A series of tests are conducted, and a nonlinear bi-viscous model is developed for the RD-1005 MR damper made by Lord Corporation. An empirical formula of equivalent viscous coefficient is derived for the MR damper under different input voltages, exciting frequencies and displacement amplitudes. Taking account of the sag, bending stiffness and inclination angle of cables, the design method for mitigating cable vibration by using viscous dampers is studied, and the Pacheco's design curve is revised based the new findings. Finally, an optimal design method is proposed for mitigating cable vibration by using MR dampers. Field test results show that the proposed method can be useful for bridge design.