摘要
为明确长安街西延永定河大桥斜拉索的风雨振特性,提出有效的减振措施;进行斜拉索风雨振计算分析,并通过风洞试验分析风速和雨强对斜拉索风雨振的影响;研究不同阻尼比和斜拉索表面缠绕双螺旋线的减振效果。结果表明:该桥大部分斜拉索在不采取减振措施的情况下有发生风雨振的可能;斜拉索风雨振的振幅随着风速的增大先增大后减小,随着雨强的增大逐渐减小;增大阻尼比能有效减小斜拉索风雨振的振幅。建议该桥斜拉索安装阻尼器时,阻尼比不小于0.9%;当螺旋线的直径为1.2mm时,单根螺旋线的间距取6倍的斜拉索直径;当单根螺旋线的间距为12倍的斜拉索直径时,螺旋线的直径取2.0mm。
To examine the characteristics of rain-wind induced vibration on stay cables of Yongding River Bridge on West Expansion of Chang’an Avenue and to figure out effective vibration suppression measures,the rain-wind induced vibration of stay cables were calculated and analyzed.And wind tunnel tests were also done to analyze the influence of wind speed and rain intensity on the rain-wind induced vibration of stay cables,and the vibration suppression effects of setting different damping ratios and adding double helix ribs on surface of stay cables were studied.The results show that the majority of stay cables are prone to rain-wind induced vibration when no vibration measures are taken.As the increase of wind speeds,the amplitude of the rain-wind induced vibration of stay cables shows the sign of turning from increasing to decreasing,but the heavier rains often bring decreased amplitude of rain-wind induced vibration.It is suggested that the damping ratio of dampers should be no less than 0.9%.When the diameter of the helix ribs is 1.2 mm,the spacing of individual helix ribs should take the value of six times of the diameter of stay cables.However,when the spacing of individual helix ribs is about 12 times of the diameter of stay cables,the diameter of helix rib should be 2.0 mm.
作者
张为
刘庆宽
刘小兵
ZHANG Wei;LIU Qing-kuan;LIU Xiao-bing(Beijing General Municipal Engineering Design&Research Institute Co.,Ltd.,Beijing 100082,China;Wind Engineering Research Center,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)
出处
《世界桥梁》
北大核心
2020年第3期48-52,共5页
World Bridges
基金
国家自然科学基金面上项目(50878135)。
关键词
斜拉索
风雨振
风洞试验
风速
雨强
减振措施
阻尼比
螺旋线
stay cable
rain-wind induced vibration
wind tunnel test
wind speed
rain intensity
vibration suppression measure
damping ratio
helix rib
