Power Spectral Density Analysis of Track Irregularity of CWR Track of Qinghai-Tibet Railway

Abstract

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