斜拉索杠杆质量阻尼器减振性能参数化研究  

Parameterized research on vibration reduction characteristics of inclined-cable using lever mass damper

作　　者：王波[1,2] 汪正兴[1] 江祥林 

机构地区：[1]中铁大桥局集团武汉桥梁科学研究院有限公司,湖北武汉430034 [2]武汉大学土木工程博士后流动站,湖北武汉430072 [3]江西省交通科学研究院,江西南昌330038

出　　处：《世界地震工程》2013年第2期117-123,共7页World Earthquake Engineering

基　　金：江西省交通运输厅科技项目(2010C00005);武汉市青年科技晨光计划项目(2013070104010037)

摘　　要：为探讨杠杆质量阻尼器(LMD)对超长斜拉索的综合减振效果,推导了斜拉索-LMD系统的状态向量方程及LMD的等效阻尼力模型,求得了斜拉索前15阶模态的对数衰减率。以LMD索夹安装高度位置比、LMD杠杆放大倍数及LMD与斜拉索模态质量比为状态变量进行了参数化分析及模型试验研究。研究结果表明:LMD由于惯性项、刚度项及阻尼项的三重反馈作用,同时由于杠杆的调节放大作用,其减振效果优于相同安装高度的粘性剪切型阻尼器(VSD)。斜拉索各阶模态的对数衰减率随着LMD索夹安装高度位置比的增加而增大,增大LMD杠杆放大倍数,斜拉索各阶模态对数衰减率随之增大,且所需阻尼参数值减小,随着LMD与斜拉索模态质量比的增大,斜拉索低阶模态与高阶模态对数衰减率增减趋势不一致,存在系统最优模态质量比。LMD综合减振效果较好,可为千米级甚至更大跨度的斜拉桥拉索减振提供有效的解决方案。To investigate the comprehensive vibration reduction of inlined - cable using lever mass damper, the state vector equation of cable - LMD system and the LMD equivalent damping force model were deduced, and the logarithmic decay rate of the cable＇ s first 15 modes was obtained. Taking installation height ratio of LMD, lever amplification of LMD and modal mass ratio between LMD and cable as the state variables, the parametric analysis and model test were conducted. The results show that： due to feedback function of inertia, stiffness and damping, the lever＇ s adjusting amplification effect, the vibration reduction effect effect of LMD is better than the viscous shearing damper with same installation height. Increasing the installation height ratio of LMD, the cable modal logarithmic decay rates are also enlarged, increasing the LMD lever amplification, the cable modal logarithmic decay rate are increased, and the required damping parameter value is reduced, increasing the modal mass ratio between LMD and cable, the cable modal logarithmic decay rate change trend of the low order mode and the high order mode is inconsistent, and there is a system＇ s optimal modal mass ratio. The LMD has a better comprehensive vibration reduction effect, and can provide a reliable solution for the stayed cable vibration control of a cable - stayed bridge with thousand -meter scale even greater span.

关 键 词：斜拉索 杠杆质量阻尼器 对数衰减率 模态质量比 

分 类 号：TU311[建筑科学—结构工程] O327[理学—一般力学与力学基础]