京沪高速铁路南京大胜关长江大桥风—车—桥耦合振动分析

Analysis on the Wind-Vehicle-Bridge Coupling Vibration for Nanjing Dashengguan Yangtze River Bridge of Beijing-Shanghai High-Speed Railway

用多刚体结构模拟车辆，空间梁单元模拟桥梁，轮轨密贴假定和蠕滑理论处理轮轨间作用力，以快速谱分析法模拟风速场，对桥梁子系统施加静风力和抖振风力，对车辆子系统施加稳态风力，采用实测桥梁3分力系数，建立风-车-桥耦合动力系统。以南京大胜关长江大桥主桥6跨连续钢桁拱为例，进行0～40m·s^-1风速下风一车桥耦合系统动力分析。分析结果表明：桥梁系统的动力响应随桥面风速的增加而增大，其横向响应对风荷载的敏感程度大于竖向响应；桥面平均风速不超过15m·s^-1时，高速列车可以设计速度安全通行桥梁；风速在15-20m·s^-1时，安全通过桥梁的车速不应超过240km·h^-1;风速在20-25m·s^-1时，车速不应超过180km·h^-1；风速在25-30m·s^-1时，车速不应超过160km·h^-1；风速超过30m·s^-1时，不能保证列车安全通过桥梁。

The vehicle is modeled by rigid dynamics method. The bridge is modeled by spatial beam elements. The wheel-rail interaction force is defined by wheel-rail corresponding assumption and creep theory. The wind velocity field is simulated by fast spectrum analysis method. The bridge subsystem is acted by static wind force and turbulent wind force. The vehicle subsystem is acted by steady wind force. The measured tri-component aerostatic coefficient is adopted in calculation, thus the wind-vehicle-bridge coupling system is established. The wind-vehicle-bridge dynamic characteristics of the 6-span steel arch in Nanjing Dashengguan Yangtze River Bridge are analyzed under the wind velocity of 0~40 m·s^-1. The result shows that the dynamic response of bridge subsystem increases with the increase of the deck wind velocity, whose sensitivity in lateral direction is larger than that in vertical direction. The higb-speed trains can safely pass the bridge with the design speed when the deck wind velocity is 15 m·s^-1or lower; or no more than 240 km· h^-1 when the deck wind velocity is 15~20 m·s^-1; or no more than 180 km· h^-1 when the deck wind velocity is 20~25 m·s^-1 ; or no more than 160 km· h^-1 when the deck wind velocity is 25---30 m·s^-1 ; the trains can not safely pass the bridge when the deck wind velocity is above 30 m·s^-1.