摘要
风雨环境中斜拉索表面形成的水线及其周向摆动在索的风雨振中起着关键的作用。实桥的斜拉索表面形成的水线位置沿索轴向有可能不均一,各部分水线的摆动可能存在位相差。该文通过振动分析得到水线摆动对索振动阻尼贡献的关系式,利用风洞试验测试了索的气动力并算得颤振导数,按水线位置分布均一和不均一,将水线分别简化为一段直线模型和两段位置不同的直线模型,分析了均一水线摆动和不同位相差的两段直线形水线摆动对索振动的影响,结果表明:单一水线摆动是否促使索变得气动不稳定,取决于水线摆动与索振动之间的位相差;不均一水线摆动时,两水线的位相差越小,摆动的效果越明显,位相差越接近180°,两水线摆动效果越趋向于相互抵消,此时水线的作用主要由水线摆动范围的中心位置决定。
The tangential movement of water rivulet has significant effects on the rain-wind induced vibration of stay-cables. For real cables in rain-wind weather, it is likely that water rivulet is non-uniform along cable axis and the phase lag between each part of rivulet movement will be incurred. In this paper, the effect of damping of rivulet movement on cable vibration was investigated, and aerodynamic derivatives were obtained by means of wind tunnel tests. Water rivulet models were simplified as one segment of straight line for uniform case, and two segments for non-uniform case. For uniform case, water rivulet movement tends to stabilize or destabilize cable vibration, depending on the phase lag between water rivulet movement and cable vibration. For non-uniform case, the phase lag between the two water rivulet movements has significant effect on cable vibration, the smaller the phase lag, the stronger the cable vibration. When phase lag approaching 180~, the two rivulet movements tend to cancel out each other, and their effect will depend upon the central position of movement range.
出处
《工程力学》
EI
CSCD
北大核心
2008年第6期234-240,共7页
Engineering Mechanics
基金
河北省自然科学基金项目(E2008000442)
河北省留学归国人员项目(冀人办[2007]20号)
石家庄铁道学院科研专项项目(211043)
关键词
斜拉索
风雨振
水线
不均一
摆动
位相差
stay-cables
rain-wind induced vibration
water rivulet
non-uniform
movement
phase lag
