青藏铁路无缝线路试验段轨道不平顺功率谱分析

PSD analysis of track irregularity of continuously welded rail track in test zone of qinghai-tibet railway

以青藏铁路静态轨检车实测轨道不平顺数据为统计样本，基于样本平稳性检验，采用快速傅里叶变换方法进行样本空间的谱估计，并由MATLAB编程得到轨道不平顺谱密度。通过对比分析，发现青藏铁路无缝线路试验段建成1年多并通车近4个月以后，轨道高低、方向和轨距不平顺特征未发生明显改变，轨道状态基本稳定；试验段轨道状态良好，与我国一级干线轨道具有相似的平顺性特征；无缝线路轨道高低和方向2～4m短波不平顺优于有缝线路轨道。

The specimen used by this paper was collected by static track geometry inspection car from Qinghai - Tibet railway. Based on the stationarity test of the specimen, the Fast Fourier Transform （FFT） method was used to evaluate the spectrum of the whole specimen space. The power spectrum density （PSD） of track irregularity was obtained by MATIAB program. By the contrast analysis, it is found that the character of track vertical profile irregularity, track alignment irregularity and track gauge irregularity of continuously welded rail （CWR） track test zone in Qinghai - Tibet railway change little after final completion for more than one year and used for nearly four month. It is indicated that the track state in test zone is stable. The track in test zone is in good working order and its irregularity character is similar as that of Chinese main railway line. The 2 - 4 short wave irregularity of CWR track vertical profile and track alignment are obviously better than those of joined track.