高速动车组转向架构架动应力特征研究

Study on Dynamic Stress Characteristics of Bogie Frame of High-speed EMU

针对动车组转向架构架在不同服役条件下的结构可靠性问题,开展基于线路跟踪实测数据的转向架构架动应力特征研究。首先基于构架实际线路跟踪测试数据对构架进行疲劳强度评估;在此基础上,分析不同工况下构架的动应力特征,进而研究构架动应力主频来源以及不同速度级和线路条件等因素对构架动应力的影响。结果表明:进出站工况下,构架在道岔区段产生较大的应力,且存在频率范围较宽的高能量振动,匀速工况下构架应力主频分别对应周期性激扰频率;构架各测点等效应力幅值随速度等级提高而增大,其中横侧梁连接区域测点增大程度在37%以上;构架在京广线上的动应力水平高于京沪线,且部分路段损伤值存在明显较大的现象;随着曲线半径增大,各测点等效应力整体呈减小趋势。研究结果可为构架的优化设计及疲劳强度分析提供一定理论参考。

Aiming at the structural reliability of an EMU bogie frame under different service conditions,a study on the dynamic stress characteristics of the bogie frame based on the measured data of line tracking was carried out.The fatigue strength of the bogie frame is evaluated based on the actual line tracking test data.On this basis,the dynamic stress characteristics of the bogie frame under different working conditions are analyzed,and then the main frequency source of dynamic stress and the effects of different speed levels and line conditions on dynamic stress are studied.The results show that under the condition of entering and leaving the station,the bogie frame produces large stress in the switch section,and there is high-energy vibration with a wide frequency range.Under the condition of uniform speed,the main frequency of the dynamic stress corresponds to the periodic excitation frequency respectively.The equivalent stress amplitude at each measuring point increases with the increase of speed level,and the increase of measuring points in the connection area of transverse and side beams is more than 37%.The dynamic stress level of the bogie frame on the Beijing-Guangzhou line is higher than that on the Beijing-Shanghai line,and the damage value of some sections is obvious.With the increase of curve radius,the equivalent stress amplitude at each measuring point decreases as a whole.The research results can provide a certain theoretical reference for the optimization design and fatigue strength analysis of the bogie frame.