无砟轨道板端裂缝扩展有限元分析

FINITE ELEMENT ANALYSIS OF CRACK EXPANSION AT THE END OF BALLASTLESS TRACK SLAB

为研究温度荷载作用下,无砟轨道板端裂缝的扩展与受力特性,文中基于扩展有限元法,采用有限元软件对无裂缝、初始裂缝轨道在整体升温作用下的性能分析。获得了轨道板在温度荷载作用下的裂缝发展过程及应力分布。结果表明带裂缝轨道板在整体升温作用下,裂缝沿横向扩展而沿纵向几乎不发展,裂缝处由于存在应力集中现象,带裂缝轨道板峰值应力远大于无裂缝轨道板。为无砟轨道的裂缝扩展研究和修复提供依据。

In order to study the expansion and stress characteristics of cracks at the end of ballastless track slab un⁃der temperature loading,the performance analysis of uncracked and initially cracked track under the overall warm⁃ing effect using finite element software based on the extended finite element method is presented in the paper.The crack development process and stress distribution of the track plate under the temperature load are obtained.The re⁃sults show that the cracked track slab expands along the transverse direction but hardly develops along the longitudi⁃nal direction under the overall warming effect;the peak stress of the cracked track slab is much higher than that of the uncracked track slab due to the stress concentration phenomenon at the crack.This paper may provide the refer⁃ence for the study and repair of crack propagation in ballastless tracks.