垂度拉索-惯质阻尼器体系的减振分析

Vibration reduction analysis of a cable-inertial damper system with sag

提出一种利用齿轮齿条、惯质元件和黏滞阻尼元件组合的拉索用新型惯质阻尼器,给出了阻尼器各元件参数的理论设计方法,并指出了其耗能原理。利用理论推导结合数值计算的方法给出其单体耗能性能,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,给出了考虑垂度拉索-惯质阻尼器体系的模态阻尼比计算公式。针对某实际拉索,使用无量纲化分析方法,给出了实索惯质阻尼器的设计参数及相应的拉索模态阻尼比。研究了同一惯质阻尼器参数对不同拉索振动模态的减振效果。结果表明,当有垂度拉索在惯质或阻尼增大时会趋近于本阶次的嵌固频率。针对某实际超长拉索,当目标减振模态阶数不太多时,经过惯质、黏滞阻尼及安装位置等多参数调谐之后,可获得优于现有黏滞阻尼器的广谱减振效果。

In this paper,a new type of inertial damper for cables with a combination of rack and pinion,inertial element,and viscous damping element was proposed.A theoretical design method of each element parameter of the damper was given,and the principle of energy consumption was pointed out.By using theoretical derivation combined with a numerical calculation method to give its single energy dissipation performance,the in-plane motion equation of the cable-inertial damper system was established.By using the complex modal analysis method,the cable-inertia considering the sag was given.Formula for calculating the modal damping ratio of a mass damper system was given.For a certain actual cable,by using the dimensionless analysis method,the design parameters of the real cable inertial damper and the corresponding cable modal damping ratio were given.The damping effect of the same inertial damper parameters on different cable vibration modes was studied.The results show that the cable with sag will approach the fixed frequency of this order when the inertia or damping increases.For an actual super-long cable,when the order of the target vibration-damping mode is not too much,after multi-parameter tuning of inertia,viscous damping and installation position,a broad-spectrum damping superior to the existing viscous damper vibration effect can be obtained.