地铁车辆天线梁振动加速度及动应力试验

Test study on vibration and dynamic stress of subway vehicle's antenna beam

为考察地铁车辆天线梁的安全可靠性,基于在线测试进行了ATP吊座处振动加速度和疲劳薄弱点的动应力研究.采用有限元法对天线梁进行随机振动分析确定疲劳薄弱部位,从而为电阻应变片布置方案的选取提供依据.在空车和超员工况下获得ATP吊座处的加速度-时间历程和疲劳薄弱部位的应变-时间历程,对所采集的加速度信号进行频谱分析,得到ATP吊座处3个方向的振动频率和加速度谱.采用雨流计数法和结构损伤一致性原则对应变-时间历程分析,得到各测点的应力谱和等效应力幅.结果表明:整个过程ATP吊座处的加速度和疲劳薄弱部位的应力的小幅值出现次数占整个过程的绝大部分,而出现大幅值的次数很少;在空车时ATP吊座处的3个方向的振动加速度大于超员的状况,疲劳薄弱点的等效应力幅是超员的大于空车的工况.

In order to investigate the safety and reliability of subway vehicle＇s antenna beam, accelera- tion on ATP （Automatic Train Protection）hanging seat and dynamic stress of fatigue weak region are carried out by online test. Random vibration analysis is processed by FEM （Finite Element Method）to determine the layout scheme of the resistance strain gauges. History of acceleration-time and stress- time are measured online in different conditions of empty and overstaffing. Dealing with history of ac- celeration-time by signal spectrum analysis, frequency distribution and acceleration spectrum are ac- quired; stress spectrum and equivalent stress amplitude of each measuring point are acquired by rain flow count and damage consistency through history diagram of stress-time. The results show that small value of acceleration on ATP hanging seat and dynamic stress of fatigue weak region is the majority of total number, and large amplitude is rare; Vibration of ATP hanging seat on empty conditions is higher than overcrowding＇ s result, the equivalent stress amplitude on fatigue weak region on overcrowding conditions is higher than the empty.