Sun Bing-nan, Wang Zhi-gang, Ko J M, Ni Y Q
Department of Civil Engineering, Zhejiang University, Hangzhou 310027, China.
J Zhejiang Univ Sci. 2003 Jan-Feb;4(1):13-20. doi: 10.1631/jzus.2003.0013.
This paper presents a nonlinear dynamic model for simulation and analysis of a kind of parametrically excited vibration of stay cable caused by support motion in cable-stayed bridges. The sag, inclination angle of the stay cable are considered in the model, based on which, the oscillation mechanism and dynamic response characteristics of this kind of vibration are analyzed through numerical calculation. It is noted that parametrically excited oscillation of a stay cable with certain sag, inclination angle and initial static tension force may occur in cable-stayed bridges due to deck vibration under the condition that the natural frequency of a cable approaches to about half of the first model frequency of the bridge deck system. A new vibration control system installed on the cable anchorage is proposed as a possible damping system to suppress the cable parametric oscillation. The numerical calculation results showed that with the use of this damping system, the cable oscillation due to the vibration of the deck and/or towers will be considerably reduced.
本文提出了一种非线性动力学模型，用于模拟和分析斜拉桥中由于支承运动引起的一种斜拉索参数激励振动。模型中考虑了斜拉索的垂度、倾角，在此基础上，通过数值计算分析了这种振动的振动机理和动力响应特性。值得注意的是，在斜拉索固有频率接近桥面板系统一阶模态频率的一半的情况下，由于桥面振动，具有一定垂度、倾角和初始静拉力的斜拉索可能会发生参数激励振动。提出了一种安装在索锚上的新型振动控制系统作为一种可能的阻尼系统来抑制索的参数振动。数值计算结果表明，使用这种阻尼系统，由于桥面和/或桥塔振动引起的索振动将大大降低。
