TITLE:
Study on Vibration Characteristics of Stay Cable-Nonlinear Viscous Damper System
AUTHORS:
Xiaolong Li, Kai Zhao
KEYWORDS:
Stay Cable, Vibration, Nonlinear Viscous Damper, Damper Design Method, Parametric Analysis
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.12 No.2,
April
18,
2022
ABSTRACT: Tension cables are easily prone to generating varied vibrations under the
action of external loads, which adversely affects the safety of bridges.
Therefore, it is necessary to take effective measures to suppress the vibrations
of tension cables. Cable end dampers are widely used in vibration reduction for
cable-stayed bridges due to their convenient installation and low costs.
However, the previous studies on the tension cable-viscous damper systems
mostly adopt the linear method, and the
weakening effect of the flexibility of mounting brackets on the damper
vibration reduction is not sufficiently taken into account. Therefore, this
paper adopts the improved Kelvin model to conduct the derivation, solution, and
parametric analysis of vibration equations for the stay cable-nonlinear viscous
damper systems. The results of parametric analysis show that the maximum modal
damping ratio that can be obtained by cables and the corresponding optimal
damping coefficient of dampers are correlated with the damping nonlinear
coefficient α, stiffness nonlinear coefficient β, vibration order n, installation position a/L,
and stiffness coefficient μ, etc.; among them, n damping nonlinear
coefficient α and stiffness nonlinear coefficient β are the key
parameters that affect the parameter design of dampers, where damping nonlinear
coefficient α mainly controls the optimal damping coefficient and
stiffness nonlinear coefficient β mainly controls the maximum damping
ratio. Based on the parametric analysis, the design principles of dampers and
value requirements of key parameters under different vibration suppression
objectives are presented.