秦沈客运专线板式无砟轨道不平顺功率谱分析

PSD analysis of slab track irregularity of Qinhuangdao-Shenyang dedicated passenger railway line

以秦沈客运专线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FFT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和相关函数。通过对比分析,发现无砟轨道不平顺优于有砟轨道,高低和方向不平顺尤为突出;在8 m以下波段内无砟轨道不平顺很好,无明显周期性成分;无砟轨道左右股钢轨横向不平顺控制均匀;左右两轨高低不平顺相关性较强,方向不平顺相关性较弱。基于样本的总体平均,运用非线性最小二乘拟合优化算法,得出无砟轨道不平顺谱密度拟合曲线参数值,对于研究我国无砟轨道不平顺功率谱有参考价值。

The statistic specimen was collected by track geometry inspection car from Qinhuangdao - Shenyang dedicated passenger railway line. Based on the stationarity test of the specimen, Fast Fourier Transform （FFT） method was used to evaluate the spectrum of the whole specimen space. The power spectrum density （PSD） and related functions of track irregularity were obtained by MATLAB program. By the contrast analysis, it is found that ballastless track irregularity is better than ballasted track irregularity, especially track vertical profile irregularity and track alignment irregularity. Ballastless track irregularity with wavelength less than 8 m is very good, and there is no remarkably periodic component. The left and right rail lateral irregularity of ballastless track is u- niform. The correlation of vertical profile irregularity of left and right rail is strong, and the correlation of alignment irregularity is weak. Based on total average of the specimen of the track irregularity, the parameter values of PSD fitting curve for ballastless track irregularity are obtained by the nonlinear curve -fitting algorithm in the least- squares sense, which has referencing value to study ballastless track irregularity PSD.