地面沉降对路基上单元板式无砟轨道平顺性的影响分析

Influence of Land Subsidence on the Regularity of the Ballastless Track with Unit Slabs

为揭示地面沉降对路基上单元板式无砟轨道平顺性的影响规律,通过建立路基上板式无砟轨道-路基有限元实体模型,充分考虑无砟轨道和路基的特性及其之间的接触方式,改变轨道结构层厚度和粘结方式,以此来进行地面沉降幅值、轨道结构层厚度和结构层间离缝对轨道不平顺的影响的研究。结果表明:地面发生沉降时,无砟轨道会发生跟随性的沉降,从上到下各层沉降值依次增大,且地面沉降幅值越大,轨道不平顺越明显;轨道结构层厚度越大,地面沉降对轨道平顺性的影响越小;轨道结构层间离缝对轨道平顺性有很大影响,尤其是无砟轨道与道床之间出现离缝时。

To reveal the influence of land subsidence on the regularity of the ballastless track with unit slabs, the finite element solid model of track-subgrade was established regarding the slab ballastless track on subgrade. Further, through fully considering the characters of both the ballastless track and the subgrade as well as their interface mode, and then through setting up the different track structure layer thicknesses and the different bonding modes, the influences on the track irregularity were studied respectively caused by different land subsidence magnitudes, by different track structure layer thicknesses, and by the de-bonding between structure layers. The results show that when the land subsidence occurs, the subsidence of the ballastless track will follow it, and the subsidence magnitude of every track layer will gradually increase from top layer to bottom layer. The irregularity of the track will be more obvious as the magnitude of the land subsidence increases; and the larger the track structure thickness is, the smaller the negative influence of land subsidence on the track regularity becomes. Moreover, the de-bonding between track structure layers has significant negative influence on the regularity of the track, especially the de-bonding between the ballastless track and the track bed.