Abstract: A new type of inertial damper for cable was proposed, which was composed of gear rack, inertial element and viscous damping element. The dampers theoretical design method was given, and its energy dissipation mechanism was pointed out. The cable-inertial damper systems in-plane motion equation was established. Using the complex modal analysis method, the single-order vibration reduction performance analysis and multi-order broad-spectrum vibration reduction performance analysis of cable-inertial damper system was carried out. The results show that the inertial damper has a good damping effect on the cables single-order vibration, with the first-order vibrations modal damping up to 6.14, the second-order vibrations modal damping up to 5.17 and the third-order modal damping up to 3.66. The single-order damping capacity of the inertial damper is one order of magnitude higher than the ordinary viscous damper. In terms of broad-spectrum vibration reduction, such as considering the first four vibration modes, when the mass ratio μ is at 0.1 and 0.2, the vibration reduction effect of inertia damper is greatly improved compared with that of ordinary viscous damper. When the damper is installed at 3% cable length, the first four order broad-spectrum vibration reduction effect increases by 14.6%. However, attention should also be paid to the “embedding effect” of inertial damper on high-order vibration modes. When the mass ratio μ is at 0.5 and 0.8, the inertial damper has a suppression effect on the higher-order modal damping. In this case, the first eight order of broad-spectrum vibration reduction design cannot be carried out. According to the analysis in this study, after multi-parameter tuning such as the inertial, viscous damping coefficient and installation position, a corresponding inertial damper is designed for the cable in a practical project and its broad-spectrum characteristics are also better than those of the ordinary viscous dampers, which verifies the feasibility of the application in real bridge.

Key words: bridge engineering; cable damping; complex mode analysis; new inertial damper; damping effect; broad-spectrum damping; the real bridge damper application

摘要： 提出了一种利用齿轮齿条、惯质元件和黏滞阻尼元件组合的拉索用新型惯质阻尼器，给出了阻尼器的理论设计方法，并给出了其耗能机理。建立了拉索-惯质阻尼器体系的平面内运动方程，使用复模态分析法对拉索-惯质阻尼器体系进行了单阶减振性能分析及多阶广谱减振性能分析。结果表明：惯质阻尼器对拉索的单阶振动有很好的减振效果，其一阶振动的模态阻尼可达6.14，二阶振动的模态阻尼为5.17，三阶振动的模态阻尼为3.66，其单阶减振能力比普通黏滞阻尼器提高了一个数量级；在广谱减振方面，如考虑前四阶振动模态，在质量比μ为0.1、0.2时，惯质阻尼器的减振效果相比普通黏滞阻尼器有大幅提高，当阻尼器安装位置为3%索长时前四阶广谱减振效果增幅达14.6%；但惯质阻尼器对高阶振动存在“嵌固效应”，在质量比μ为0.5、0.8时，惯质阻尼器对高阶的模态阻尼产生了抑制效果，在此种情况下无法进行前八阶的广谱减振设计；对惯质、黏滞阻尼系数及安装位置进行多参数调谐后，为某实际工程中的拉索设计了相应的惯质阻尼器，其广谱特性优于现有黏滞阻尼器，验证了实桥应用的可行性。

关键词: 桥梁工程；拉索减振；复模态分析；新型惯质阻尼器；减振效果；广谱减振；实桥阻尼器应用