桥上CRTS Ⅱ型板式无砟轨道均匀温度研究

摘要

Thermal sensors have been installed on a curved bridge of high-speed rail.By means of carrying out 2 years monitor of CRTS II ballastless track,the time-varing rules are revealed.Through daily temperature data calculated from the measured data by using difference method of time series,the time-varing curve of uniform temperature,which represents the trend of bulk temperature change laws,can be obtained.Then,the rules of track temperature variance with atmospheric temperature are effectively reflected.In order to examine the change law of uniform temperature,Fourier curve fitting and high-moment statistical model are utilized,and the overall curve representing the changing laws of track temperature are put forward.The results show that the track uniform temperature appeared trigonometric development with a tropical year (namely 365 days) as a cycle,and the regression parameters can represent its median,amplitude and phase-difference.The entire section of the track can be analyzed as a whole,because the fitting results among test points are close,which indicates that the changing laws of track uniform temperature can be expressed by its overall curve.By using high-moment statistical model to analyze the differences between overall curve and its fitting curve,the representative value of overall curve with probabilistic guarantee can be obtained.%在某客运专线曲线段桥上设置温度传感器,通过对CRTS Ⅱ型板式无砟轨道进行长达两年的监控,得到其时变规律,利用时间序列差分法求得测点日平均温度,得到代表整体温度变化趋势的均匀温度时程曲线,有效反映了结构温度随大气的季节性变化规律.基于傅立叶曲线拟合及高阶矩统计模型研究其规律,提出无砟轨道整体的均匀温度变化规律.结果表明,结构各测点均匀温度呈现以365 d为周期的三角函数变化规律,其拟合参数可分别表示均匀温度变化规律中的中位值、幅值及相位差;各测点间的均匀温度拟合结果差异较小,可将轨道全截面作为一整体分析,用其统一温度代表轨道整体的均匀温度变化规律;通过高阶矩概率统计模型对统一温度分析,可得到具有概率保证的均匀温度变化方程.