运动水线三维连续弹性拉索风雨激振理论模型  

An Analytical Model of Rain-wind-induced Vibration of Three-dimensional Continuous Stay Cable with Actual Moving Rivulet

作　　者：李寿英[1,2] 顾明[2] 陈政清[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]同济大学桥梁工程系,上海210092

出　　处：《湖南大学学报（自然科学版）》2009年第2期1-7,共7页Journal of Hunan University:Natural Sciences

基　　金：国家科技支撑计划资助项目(2006BAJ03B04);国家自然科学基金资助项目(50708035);中国博士后科学基金资助项目(20060400873)

摘　　要：采用已有的水线气动力数据,假设拉索和水线之间相互作用力为库仑阻尼力和线性阻尼力,推导了三维连续弹性拉索和三维连续水线的运动偏微分方程,采用数值方法进行求解,得到三维连续拉索和三维连续水线的风雨激振响应规律.结果表明:当三维连续拉索大部分截面处于易于起振的风速区域时,水线在这些拉索截面形成并处于竖向平均气动力系数的突降区,三维连续弹性拉索发生大幅振动.拉索的振动含有多阶拉索固有频率成分,且水线除了在拉索固有频率处有能量峰值外,在5 Hz以下的其他频段均有少量的能量分布.另外,拉索和水线的库仑阻尼力增大,拉索振幅增大;当拉索模态阻尼比达到0.5%时,可有效地抑制拉索的风雨激振振动.Assuming the interactions between the cable and the rivulet as Coulomb and linear damping forees, the equations governing three-dimensional continuous stay cable and three-dimensional continuous rivulet were derived. And these partial differential equations were solved in numerical method to obtain the responses of the cable and the rivulet. When the velocities at the range of the cable height were mostly prone to rain-wind induced vibration, large oscillation amplitude of the three-dimensional continuous stay cable appeared. The vibration of the cable included several natural frequencies, and the energies of the rivulet also mainly focused on several natural frequencies of the continuous cable, but there existed a little energy distribution on all frequencies under 5 Hz. When the Coulomb damping force between the cable and the rivulet increased, the amplitude of the cable increased accordingly. If the damping ratio of the three-dimensional continuous cable was up to 0.5 %, the rain-wind induced vibration could be perfectly mitigated.

关 键 词：三维连续拉索 风雨激振 理论分析 运动水线 库仑阻尼力 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] V211.7[交通运输工程—道路与铁道工程]