为实现对高速列车车轮高阶不圆的实时检测,研究了轴箱高频振动与车轮不圆的频谱特征和映射关系,采用频域积分方法对车轮不圆的幅值和阶次进行辨识.首先,通过静态测试和台架试验,研究我国高速铁路车轮多边形、钢轨波磨和轨道模态的表现形式;其次,通过高速列车长期服役性能跟踪试验,掌握转向架轴箱振动的时频特征和演化规律;最后,以现场出现车轮 20阶多边形的车辆为研究对象,提出基于频域积分的车轮不圆阶次和幅值辨识方法.研究结果表明:CRTS-Ⅱ型轨道板钢轨三阶弯曲频率为 592 Hz;列车以 300 km/h运行时,20阶车轮多边形和 136 mm波长钢轨波磨的响应频率分别为 580 Hz和 613 Hz;钢轨模态、车轮多边形以及钢轨波磨的振动主频较为集中,轴箱高频振动幅值随车速和镟后里程的增大而增大;采用加速度频域积分方法,从理论上可实现对车轮不圆幅值和阶次的辨识;基于线路实测轴箱加速度的 20阶车轮多边形辨识结果与静态测试值相对误差不超过5%.
In order to realise the real-time detection of wheel out-of-roundness(OOR)for high-speed trains,the spectral characteristics and mapping relationship between the axlebox high-frequency vibration and the wheel OOR are studied.The amplitude and order of the wheel OOR are identified using the frequency-domain integration method.Firstly,manifestations of the wheel polygonisation,rail corrugation and track modes of China high-speed railways are investigated through static measurements and laboratory experiments.Secondly,the time-frequency characteristics and evolution principle of the bogie axlebox vibrations are obtained through the long-term operation performance tracking test of a high-speed train.Finally,taking the 20th order wheel polygonisation as the research object,an identification approach of the wheel OOR order and amplitude is proposed based on the frequency-domain integration method.The results show that the third-order bending modal frequency of the China railway track system Ⅱ(CRTS-Ⅱ)track slab is 592 Hz.When the train is running at a speed of 300 km/h,the response frequencies due to the 20th-order wheel polygonisation and the rail corrugation with a wavelength of 136 mm are 580 and 613 Hz,respectively.The dominant frequencies of rail mode,wheel polygonisation and rail corrugation are relatively concentrated.The amplitude of high-frequency vibration of axlebox increases with the increase of vehicle speed and mileage after re-profiling.Theoretically,the amplitude and order of the wheel OOR can be identified by the integration of accelerations in the frequency domain.The relative error between the identified 20th-order wheel OOR results based on the field-tested axlebox acceleration and the static measured values is less than 5%.