地铁钢轨波磨对车辆-轨道振动及噪声特性的影响

Influence of Metro Rail Corrugation on Vehicle-Track Vibration and Noise Characteristics

钢轨波磨作为地铁线路中最为常见的轨道损伤问题之一,始终未得到根本性的解决。为研究不同轨道结构形式产生钢轨波磨后车辆内部振动噪声以及轨道结构振动的时频域特性,探究钢轨波磨对车辆和轨道的影响,对某地铁线路进行现场动静态测试,获取了钢轨波磨激励下车辆内部的振动和噪声响应以及轨道各部件的振动响应,使用时域指标统计、1/3倍频程谱分析等方法分析轨道振动响应特征和车内振动及噪声响应特征。结果表明:在小半径曲线地段,浮置板轨道产生了特征波长约为200 mm的钢轨波磨,整体道床轨道产生了特征波长约为60 mm的钢轨波磨;浮置板轨道的钢轨、道床板、隧道壁振动加速度有效值分别是整体道床的1.8、5.8倍及0.3倍;钢轨波磨对轨道振动的影响主要体现在中高频范围,在300~400 Hz附近,浮置板轨道振级从钢轨至隧道壁共衰减66 d B,而整体道床共衰减49 d B;列车通过测试区域时,转向架上方与客室中部垂、纵向振动加速度有效值基本一致,而客室中部横向振动加速度有效值约为转向架上方的2倍;车内转向架位置处的异常振动主要来源于钢轨波磨的激励,且短波长波磨所激励的车内振动及噪声更加剧烈。因此,地铁钢轨波磨产生后在轨道及车辆的振动噪声响应中均占主要成分,应及时对钢轨进行打磨处理,研究结果可为地铁工务维修提供理论指导。

Rail corrugation,one of the most common track damage problems in metro lines,has yet to be fundamentally resolved.To study the time-frequency domain characteristics of vehicle interior vibration and noise,as well as track structure vibration after rail corrugation occurs in different track structure types,and to investigate the effect of rail corrugation on vehicles and tracks,dynamic and static tests were conducted on a metro line.These tests measured the vibration and noise response inside the vehicle and the vibration response of track components under the rail corrugation excitation.Methods such as time-domain indicator statistics and 1/3-octave spectral analysis were used to analyze track vibration response characteristics and in-vehicle vibration and noise response characteristics.The results showed that on small radius curve sections,the floating slab track produced rail corrugation with a characteristic wavelength of about 200 mm,while the overall track bed produced rail corrugation with a characteristic wavelength of about 60 mm.The root mean square(RMS)value of the rail,slab,and tunnel wall vibration acceleration in the floating slab track were 1.8,5.8,and 0.3 times those of the overall track bed,respectively.The influence of rail corrugation on track vibration was mainly reflected in the mid-to-high frequency range.Around 300~400 Hz,the vibration level of floating slab track attenuated by 66 dB from the rail to the tunnel wall,while the overall track bed attenuated by 49 dB.When the train passed through the test area,the RMS values of vertical and longitudinal vibration acceleration above the bogie and in the middle of the carriage were almost the same,while the RMS value of lateral vibration acceleration in the middle of the carriage was about twice that above the bogie.The abnormal vibration at the bogie position inside the vehicle mainly originated from the excitation of the rail corrugation,and the vehicles vibration and noise were more intense under the excitation of shortwavelength corrugation.Therefore,rail corrugation in metro systems becomes a major component in both the vibration and noise response of tracks and vehicles after it occurs,and rails should be ground in time.The research results can provide theoretical guidance for metro maintenance.