高速铁路无砟轨道谱统计分析
Statistical analysis on ballastless track spectrum of high-speed railway

依据京沪和哈大高速铁路轨道不平顺实测数据,采用改进的welch周期图法计算得出原始高速铁路轨道不平顺谱密度;基于频域功率谱等效法进行轨道不平顺的时域样本数值模拟,得到了高速铁路无砟轨道轨道不平顺模拟轨道谱。研究结果表明:中国高速无砟轨道原始谱整体上优于德国高低干扰谱,更优于美国5,6级谱,可见中国高铁线路实际线路几何状态良好;适当的拟合参数和拟合模型可以使轨道随机不平顺的时域仿真结果与实测结果和频域仿真结果较好相符,能够较好地反映我国高速铁路无砟轨道不平顺特征,从而为高速列车-轨道(桥梁)时变系统随机振动分析提供良好的激振源以及为我国轨道几何形位的维修养护提供一定的理论指导。
According to the track geometry data measured from Shanghai-Beijing andhaerbin-dalian high- speed railways, the original track irregularity spectrum of high speed railway were calculated by using the improved Welch periodogram method. Based on the frequency domain power spectral equivalent method, the time domain sample of track random irregularities were numerically simulated, and then the simulation power spectrum densities (PSDs) of high speed railway ballastless track were calculated. The results show that the PSDs of ballastless track irregularity of Chinese high-speed railway are better than the low & up disturbance spectrum of German high-speed railway, even better than the 5&6 level spectrum of American high-speed railway. Thus,it can be concluded that the geometrical states of Chinese high-speed ballastless track is excellent. Based on selecting the appropriate simulation parameters and fitting model, the simulation results in time domain of stochastic railway track irregularities agree well with the measured values as well as the simulation results infrequency domain, which were able to embody the track irregularity character of Chinese high-speed railway. So they can be applied as good excitation source for high-speed vehicle-track (bridge) time- variant system random vibration analysis and as theoretical direction for the maintenance and repair of our country track geometry as well