RD-1005型磁流变阻尼器长期力学性能对比研究

Comparative study on long-term mechanical properties for RD-1005 magnetorheological dampers

磁流变阻尼器在长期使用后的力学性能是工程界关心的重要问题。选取了5个在洞庭湖大桥工作了十年的RD-1005型磁流变阻尼器进行了力学性能试验,获得了该磁流变阻尼器在不同控制电压、激振频率和振幅工况下的滞回曲线以及等效黏性阻尼系数。采用阻尼力幅值、等效黏性阻尼系数等参数与同批次新RD-1005型磁流变阻尼器进行了对比分析,评估了RD-1005型磁流变阻尼器长期工作性能。对旧阻尼器进行了拆解,探讨了该阻尼器性能退化的原因。研究表明,与新阻尼器相比,长期使用后阻尼器的力幅值平均降低率为26.9%,等效阻尼系数平均降低率为25.1%,磁流变液沉淀是该阻尼器退化的原因。

The mechanical properties of magnetorheological damper（ MRD） is an important concern in civil engineering used for a long time. The five RD-1005 MRDs which are used on stay-cable mitigating system of Dongting Lake Bridge for a decade are selected to investigate their long-term mechanical properties in this paper. By means of mechanical properties test of them by MTS-810 servo machine,mechanical curves and equivalent viscous damping coefficients of the MRDs under different exciting voltages,frequencies and amplitudes are gotten. From the point of magnitudes of damping force and the equivalent viscous damping parameter,the long-term mechanical properties of the above five RD-1005 MRDs are assessed with contrasting the same batch unused RD-1005 MRD. It is shown that the average amplitude of damper force reduces at a rate of 26. 9%,the average equivalent viscous damping parameter reduces at a rate of 25. 1%. By dismantling a long-term used MRD,it is proved that MR fluid precipitation is an important cause of the mechanical property degradation.