Journal of South China University of Technology(Natural Science Edition) ›› 2023, Vol. 51 ›› Issue (7): 61-71.doi: 10.12141/j.issn.1000-565X.220631

Special Issue: 2023年土木建筑工程

• Architecture & Civil Engineering • Previous Articles     Next Articles

Study on Natural Vibration Characteristics of Cable Network-Damper System

ZHEN Xiaoxia1 LIU Guiyuan1 DONG Chunguang2 ZHANG Zhuojie3 LI Mingyang4   

  1. 1.School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,Guangdong,China
    2.Poly Changda Engineering Co. Ltd. ,Guangzhou 510075,Guangdong,China
    3.State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang 050043,Hebei,China
    4.Foshan Transportation Science and Technology Co. Ltd. ,Foshan 528000,Guangdong,China
  • Received:2022-09-29 Online:2023-07-25 Published:2023-01-17
  • Contact: 张卓杰(1986-),男,博士,副教授,主要从事大跨度桥梁结构理论研究。 E-mail:stdzhangzhuojie@163.com
  • About author:甄晓霞(1976-),女,博士,副教授,主要从事大跨度桥梁结构动力特性及病害诊断研究。E-mail:xxzhen@scut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(52178138);the Natural Science Foundation of Guangdong Province(2021A1515012064)

Abstract:

In cable-stayed bridges, multiple stay cables are connected with cross-ties and dampers to form a multilevel cable network-damper system, which can effectively reduce the vibration of stay cables. In order to deeply understand the real dynamic behavior of the system and grasp the interaction law of cross-ties and dampers, this paper proposes a model of multilevel cable network-damper system, which simplifies the cross-ties into linear spring elements, and obtains the complex characteristic equation of the system through theoretical derivation. Next, the natural frequency and damping ratio of each order of the system are solved, and local mode parameter is proposed to characterize the local vibration degree of different modes as well as the energy distribution rules of the system, and, furthermore, auxiliary estimate the vibration consistent of the system. Then, the proposed theoretical formulation is verified by the experiment and finite element simulation. Fnially, the changes of vibration mode, frequency, local mode parameter and damping ratio of the triple-layer cable network-single damper system during the change of cross-ties from flexible to rigid are investigated, and the effects of the cross-tie stiffness and damper position on the damping ratio of the system are analyzed. The results show that the multilevel cable networks-damper system decreases the amplitude of the cables and increases damping ratio of the system; that the stiffness change of the cross-tie and the set of damper at the cable end may both lead to corresponding change of multi-order system mode shape; that the change of anchoring position of the damper at the cable end may also cause individual mode shape change.; that the damping ratio is closely related to the amplitude of the section where the damper is located and to the stiffness change of the cross-tie; and that not all mode damping ratios benefit from the damper set at the cable end. In general, the farther the damper is from the bridge deck at the cable-end anchor point, the more favorable it is for the damper to play; the greater the stiffness of the auxiliary cable, the better the integrity of the vibration system; the higher the frequency, the stronger the mutual constraint between the cables.

Key words: cable network-damper system, vibration control, damping ratio, local vibration characteristics

CLC Number: