摘要
通过风洞试验研究了台湾后龙溪桥气动稳定性;获得了混凝土梁和钢梁两种断面发生涡振的条件、涡振锁定风速范围及涡振振幅;对自然界和风洞中的风轴和体轴异同进行了区分;实测了两种断面的静气动力系数;最后进行了非线性静风荷载响应分析。研究结果表明:实桥风速达到135m/s,不会发生气动失稳;钢梁和混凝土梁断面+3°攻角时在均匀流场中会发生竖向和扭转涡振,扭转涡振风速锁定风速很高,而且范围很宽;在紊流度约为10%风场中,攻角在-3°～+3°范围内,未观测到明显涡振;由静风荷载引起的主梁附加攻角很小,风荷载非线性对主梁扭转位移和侧向位移影响很小,而对竖向位移影响相对较大,原因是竖向风荷载引起主缆刚度改变。
The aero-stability performance of Houlongxi Bridge in Taiwan was investigated via wind tunnel tests.The conditions for vortex induced vibration of concrete and steel deck sections,as well as the 1ock-in wind velocity regions and vibration amplitudes were obtained.The similarity and discrepancy between the wind-axis and the body-axis in natural field and wind tunnel were expounded and discriminated.Then the aerostatic force coefficients were measured.The non-linear aerostatic response analysis was conducted finally.The study results revealed that the real bridge will not diverge when the velocity attains 1 3.5 m/s;in smooth flows,vertical bending and torsional vortex vibration occur for two models with +3°attack angle;for torsional vortex vibration,the wind velocity is quite high and its 1ock-in region is wide;in flows with turbulence intensity of 10%,when attack angle varies form-3° to +3°,no apparent vortex can be observed;the deck added attack angle incurred by static wind 1oads is very tiny;the wind 1oad non-linearity plays negligible role on deck torsional and lateral displacement;as the vertical lift wind loads will cause the obvious change of main cable rigidity,the vertical displacement is more relevant with the wind 1oad non-linearity.
出处
《振动与冲击》
EI
CSCD
北大核心
2009年第7期77-80,共4页
Journal of Vibration and Shock
基金
国家自然科学基金(50708012)
高等学校博士点新教师基金(20070141073)
关键词
后龙溪桥
风洞试验
静风响应分析
houlongxi bridge
wind tunnel test
aerostatic response analysis
