关键词: 吊索, 悬索桥, 抗弯刚度, 双索股耦合系统模型, 减振架, 振动模态, 自振特性

Abstract: After setting the anti-vibration mount，the natural vibration characteristics of the suspension bridge sus-pender is different from that of the single cable． The vibration of the suspension bridge suspender is a comprehen-sive reflection of the interaction of the cable strands at the same lifting point． In order to study the natural vibration characteristics of suspender with the anti-vibration mount，the model of double strands coupled system considering bending stiffness of the strand was proposed． Firstly，the theoretical formula of the coupled vibration of the system was derived． Then the natural frequency was solved and verified by experiments and numerical examples． Finally，the influence of the bending stiffness of the suspender，the coupling position，the coupling stiffness of the anti-vi-bration mount，and the length of the suspender on the natural vibration characteristics of suspender was studied by taking the typical suspender of the Aizhai Bridge as the engineering background． The results show that the natural frequency of the suspender with the anti-vibration mount is obviously increased after considering the bending rigidity
of the suspender． And the shorter the cable，the bigger the increament． The anti-vibration mount ensures the con-sistency of the in-phase global modes of the two main strands． There are local modes of single strand (come in pairs when the anti-vibration mount is located at 1/2 of the strand) and out-of-phase modes between the in-phase global modes． The position of the anti-vibration mount has a significant influence on the natural vibration frequency and the mode shape of the out-of-phase modes． Compared with the rigid anti-vibration mount，the flexible anti-vi-bration mount causes decrease of the natural vibration frequency value of the out-of-phase modes． The smaller the rigidity，the greater the difference． For different lengths of suspenders，the anti-vibration mount can be regarded as a rigid anti-vibration mount when the rigidity is set to be k≥5 ×10⁶ N/m．

Key words: suspender, suspension bridge, bending stiffness, double strands coupled system model, anti-vibra-tion mount, vibration mode, natural vibration characteristics