高速铁路轨道平顺性静态长弦测量矢距差法数学模型推导及特性分析

我国高速铁路采用从德国引进的矢距差法对轨道长波不平顺进行静态管理,并在实际应用中对测量方法进行了简化。本文通过理论推导,分析矢距差法及简化矢距差法的检测原理和特性。矢距差法测量结果受测弦起算点的影响,且传递函数与起算点位置及轨道不平顺波长有关;简化矢距差法测量结果只受轨道不平顺波长的影响,计算可控性优于矢距差法;当路基出现较大局部不均匀变形时,矢距差法和简化矢距差法在评判结果上相差很大,不宜用简化矢距差法;对比检测原理与实际检测结果表明,这2种方法与车体加速度响应匹配性较差,在目前的验收管理限值下并不适用于直接对运营期高速铁路长波不平顺进行评价。

Mathematical Model Derivation and Characteristics Analysis of Vector Distance Difference Method for Static Long Chord Measurement of High Speed Railway

The vector distance difference method imported from Germany is used to manage the long wave irregularity of static track in China’s high speed railway,and the measurement method are simplified in practical application.In this paper,the inspection principle of the vector distance difference method and the simplified vector distance difference method were explained by theoretical derivation.On this basis,the calculation model was derived and its detection characteristics were analyzed.The measuring result of vector distance difference method is influenced by the starting point of the measured chord,and the transfer function is related to the location of the starting point and the wavelength of track irregularity.The measuring result of simplified vector distance difference method is only influenced by the wavelength of track irregularity,and its calculation controllability is better than the vector distance difference method.However,when inhomogeneous and large local deformation of subgrade occurs,the vector distance difference method and the simplified vector distance difference method differ greatly in the evaluation results,so the simplified vector distance difference method should not be used.By comparing the detection principle and the actual detection results,it can be seen that the two methods have poor matching with the acceleration response of the vehicle body.Therefore,it is not applicable to evaluate the long wave irregularity of high speed railway in the operation period by directly using the two methods under the current acceptance management limit.