Study on the Judgment Method for Track Regularity of the Main Railway Lines in China

The track irregularity power spectrum density(PSD) of railway was obtained based on mass of track irregularity data in recent years,and the qualitative and quantitative investigations on the judgment method of track irregularity were made.Based on the thread of establishing the general track PSD according to the railway speed grade of main railway lines in China,the qualitative judgment methods for track irregularity of the speed-increase lines with the speed of 200 and 160 km·h-1,as well as general line with the speed of 120 km·h-1,are investigated and put forward,in which the top and bottom envelope spectrum of railway PSD are defined as top and bottom delimitative spectrum.The railway PSD needed for evaluating the track is nearer to the bottom delimitative spectrum,the railway track regularity is better;contrariwise,the worse.The railway PSD of different railway lines and even different section of the same railway line are distributed in a large spectrum range due to uneven railway quality.Based on the grading management method of railway PSD,the quantitative judgment method on track regularity is investigated and put forward.Via analyzing and calculating 5 levels PSD of main railway lines,this method divides the track spectrum into 6 regions from bottom to top,that is in turn from A to F,which is defined respectively as excellent,nicer,good,mediocre,poor,very poor.