秦沈客运专线轨道谱评判方法的研究

Study on Evaluation Method of Power Spectrum Density(PSD) for the Qinhuangdao-Shenyang Dedicated Passenger Railway Line

基于2004年1月至2005年4月轨道不平顺检测数据,利用Welch改进周期图算法,分析了秦沈客运专线轨道不平顺的功率谱密度,得出平均意义上的最大值、建议值和最小值。参考国内外成熟的轨道谱线表达形式,结合试算结果,得到表达秦沈客运专线轨道谱的拟合曲线公式,并应用非线性最小二乘拟合优化算法,获得拟合轨道谱表达式的参数。据此,提出秦沈客运专线轨道不平顺功率谱质量的评判方法。该方法将轨道谱图划分成A、B、C、D4个区域,依次定义为优秀、良好、合格和不合格轨道谱线区域。这样,对于一条给定的轨道谱线,就可依此方法来评定其质量,如落入A区的部分谱线为优秀轨道谱,落入B区的部分谱线为良好轨道谱等。

The power spectrum density （simplified as PSD） of track irregularities of the Qinhuangdao-Shenyang Dedicated Passenger Railway Line （simplified as QSDPR） was analyzed by the improved Welch Periodogram Method on the basis of the track irregularity data of QSDPR from January 2004 to April 2005, and the average maximum values, proposed value and minimum values of the PSD were worked out. Referring to the mature PSD expressions published all over the world and results of test calculations, a set of fitting formulas of PSD for QSDPR was proposed. The optimization parameters of fitting track spectra were educed by the nonlinear curve-fitting algorithm in the least-squares sense. The evaluation method of PSD for QSDPR was set up on the basis of above work . This method divides the track spectrum into four regions, i. e. , A, B, C and D, which are defined respectively as excellent, good, qualified and unqualified. The quality of a given track spectrum density can be so evaluated. For example, the part of a track which spectrum density falls to the A region is regarded as the excellent track spectrum density,whereas the part falling into the B region is regarded as the good track spectrum density.