基于向量式有限元的斜拉索振动控制研究.docVIP

 基于向量式有限元的斜拉索振动控制研究# * 5 10 15 20 25 30 35 40  摘要：在拉索的锚固端附近安装阻尼器可为斜拉索提供附加阻尼，减小斜拉索的横向振动。阻尼器的设计 参数决定了阻尼器能为斜拉索提供的附加阻尼比的大小。向量式有限元是进行结构行为分析的一种新方法。 文章采用向量式有限元法，建立斜拉索的数学模型，通过给空间点增加附加作用力来模拟阻尼器对斜拉索 的作用，根据所求得的拉索响应识别系统阻尼比，从而分析了阻尼器的粘滞阻尼系数、阻尼器内刚度、阻 尼器运动部分质量、阻尼器支撑刚度，及斜拉索垂度对附加阻尼比的影响；并将分析结果与统一公式进行 了对比。表明：采用向量式有限元法模拟斜拉索的振动控制具有很好的准确性，阻尼器参数及拉索垂度对 附加阻尼比有明显影响，系统存在最优阻尼比。 关键词：斜拉索；阻尼器；模态阻尼比；向量式有限元；振动控制 中图分类号：TU 311.4 Vibration Control of Stay Cables by Vector Form Intrinsic Finite Element (VFIFE) Method NI Qiubin1, DUAN Yuanfeng1, GAO Boqing1, Ying Zuguang2, Xu Zhaodong3 (1. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058; 2. School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310058; 3. School of Civil Engineering, Southeast University, Nanjing 210096) Abstract: Transversely attached damper near the cable/deck anchorage provides supplemental damping to the stay cable, thus reducing the transverse vibration of the stay cable. The supplemental damping of the system is influenced by the parameters of the cable and the damper. Vector Form Intrinsic Finite Element (VFIFE) is a new method for analyzing the behavior of the structure. In this paper, the mathematic model of a stay cable is established using VFIFE. The effect of the damper is simulated by adding external force to the mass point of the cable. The influence of the above mentioned parameters such as damper coefficient, damper stiffness, damper mass, stiffness of damper support, and cable sag to the supplemental damping is studied. The numerical result is compared with the analytical result. It is found that applying VFIFE to the simulation of the vibration control of the stay cable could achieves high computation accuracy, and that the parameters of the damper have obvious influence on the supplemental damping, and the optimal supplemental damping exists. Key words: stay cable; damper; modal damping; VFIFE; vibration control 0 引言 随着斜拉桥跨度的不断增大，作为斜拉桥中主要受力构件之一的斜拉索也越来越长。由 于斜拉索质量轻