有砟轨道与无砟轨道动刚度特性差异研究

Research on the Difference of Dynamic Stiffness Characteristics Between Ballast Track and Ballastless Track

轨道动刚度是不同激振频率的荷载作用下,轨道抵抗变形的能力,由于有砟轨道与无砟轨道两种轨道的组成差异造成两者间存在较大动刚度差异。随着行车速度的提高、中高频段激振荷载的增加,有砟轨道与无砟轨道间的动刚度差异逐渐增大,这对于行车平顺性与结构耐久性会造成较大影响,但目前缺乏轨道动刚度的相关研究。为研究有砟轨道与无砟轨道间的动刚度差异,根据两种轨道的结构特点,建立相应的ANSYS有限元模型,通过对比分析,得出两种轨道的轨道动刚度在中低频段存在较大差异,轨下动刚度在全频段存在较大差异。为保证有砟-无砟轨道过渡段的行车平稳性与结构耐久性,需要考虑两种轨道间的动刚度过渡设计。此外,轨道动刚度特性分析可以指导高速铁路高低不平顺控制,从而保证行车平顺性。

The track dynamic stiffness is the ability of the track to resist deformation under the load of different excitation frequencies. The difference of dynamic stiffness between ballast track and ballastless track is caused by the differences of their composition and structure. The difference of dynamic stiffness characteristics between ballasted track and ballastless track increases with the increase of train speed and excitation load in medium and high frequency band. This will have a great impact on the train running smoothness and structural durability. However, there is a lack of research on track dynamic stiffness. Therefore, it is necessary to research the difference of dynamic stiffness characteristics between ballast track and ballastless track. According to the structural characteristics of ballast track and ballastless track, corresponding ANSYS finite element model is established. The comparison and analysis conclude that the track dynamic stiffness is quite different in medium and low frequency band between these two tracks, and the dynamic stiffness under the track is very different in full frequency band. In order to ensure train running smoothness and structure durability, the design of dynamic stiffness transition between the two tracks should be considered. In addition, the analysis of track dynamic stiffness can guide the control of high-speed railway irregularity, thus ensuring train running smoothness.