大跨度自锚式悬索桥钢-STC组合桥面箱形加劲梁抗风性能试验研究

以株洲枫溪大桥为工程背景,采用有限元计算和节段模型试验相结合的方法,研究大跨度自锚式悬索桥STC组合桥面钢箱加劲梁的抗风性能。研究结果表明:钢-STC组合桥面箱形加劲梁结构在-3°、0°及+3°的3种风攻角下,颤振临界风速均远高于桥位处检验风速,设计方案满足颤振稳定性要求,且有较大富余度。成桥状态下的原型断面在+3°攻角下出现了11.1~16.7 m/s与22.7~33.4 m/s两个竖弯涡振区,其中在第二个竖弯涡振区,其峰值振幅0.188 m超过规范允许值。通过对截面进行局部优化后,涡振均在规范允许值以内。节段模型测力风洞试验基于风攻角为-12°至12°范围内变化,研究了加劲梁断面的静力三分力系数的变化规律。大跨度自锚式悬索桥的钢-STC组合桥面宽幅箱形加劲梁的抗风性能试验研究为类似桥梁的设计提供依据和参考。

Experimental Research on Wind-resistant Behaviors of Stiffening Girder with Steel-STC Composite Deck in Large-span Self-anchored Suspension Bridges

Take Zhuzhou Fengxi suspension bridge as engineering background,wind-resistant behaviors of stiffening girder with steel-STC composite deck in large-span self-anchored suspension bridges are studied by finite element modelling simulation and segmental model tests.Research results show that the critical flutter wind speeds of steel box stiffening girder with steel-STC composite deck under-3°,0°and+3°wind attack angle are higher than site inspection wind speed.Two vertical bending vortex vibration regions appears in the original section under+3°wind attack angle at completion state,which are 11.1 m/s^16.7 m/s and 22.7 m/s^33.4 m/s.The peak amplitude of the second area is 0.188 m,which has exceeded the allowable area.Vortex vibrations are limited in the allowable area by changing the girder section slightly.The changing law of aerodynamic coefficients of stiffening girder section are studied under the wind attack angle range from-12°to+12°.Experimental researches on wind-resistant behaviors of stiffening girder with steel-STC composite deck in large-span self-anchored suspension bridges providing a significant evidence and reference for familiar bridges.