Scholarlink

<p>Desert railway operations are inevitably challenged by the infiltration of wind-blown sand. This increases the stiffness of the ballast bed and contributes to the corrosion of rail fasteners, ultimately compromising the safe service life of the track structure. The present study investigates the effect of laying an under-sleeper pad (USP) in sandy environments on the macroscopic and microscopic mechanical properties of railway ballast beds. By employing a discrete–continuous coupling algorithm, the interactions among ballast, sand particles, concrete sleeper, and USP are comprehensively considered. A high-fidelity, three-dimensional (3D) full-scale rigid-flexible coupling analysis model of the elastic sleeper-sandy ballast bed with polyhedral ballast particles has been established, and the model’s accuracy is validated through in situ static and dynamic tests. The results show that laying the USP reduces the lateral resistance of the ballast bed by 1.21&#xa0;kN while remaining within acceptable engineering standards. The sharing ratio consistently exhibits the highest value at the ballast shoulder, followed by the sleeper bottom, with the lowest value observed at the sleeper side. The support stiffness of the sandy ballast bed decreases by 34.56%, which significantly enhances its elasticity. The energy consumption ratio of the sandy ballast bed increases by 9.08%, reducing the direct impact of train loads on the track structure. Furthermore, laying the USP significantly reduces the maximum force chain value within the sandy ballast bed by 33.47%, thereby mitigating stress concentration phenomena. Notably, in the shallow area (0–175&#xa0;mm), the USP exhibits a markedly vibration-reduction effect. Therefore, it is recommended that the USP be applied in severe sandy ballast bed sections to improve the elasticity of the ballast bed, reduce stress concentration, and diminish vibration effects.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Influence of laying under-sleeper pads on the macroscopic and microscopic mechanical properties of sandy railway ballast bed

  • 期刊论文

  • 发表日期：

    2025年8月11日

查看全文
  • Yihao Chi,
  • Hong Xiao,
  • Yang Wang,
  • Zhihai Zhang,
  • Weize Zhao,
  • Mahantesh M. Nadakatti

摘要

Desert railway operations are inevitably challenged by the infiltration of wind-blown sand. This increases the stiffness of the ballast bed and contributes to the corrosion of rail fasteners, ultimately compromising the safe service life of the track structure. The present study investigates the effect of laying an under-sleeper pad (USP) in sandy environments on the macroscopic and microscopic mechanical properties of railway ballast beds. By employing a discrete–continuous coupling algorithm, the interactions among ballast, sand particles, concrete sleeper, and USP are comprehensively considered. A high-fidelity, three-dimensional (3D) full-scale rigid-flexible coupling analysis model of the elastic sleeper-sandy ballast bed with polyhedral ballast particles has been established, and the model’s accuracy is validated through in situ static and dynamic tests. The results show that laying the USP reduces the lateral resistance of the ballast bed by 1.21 kN while remaining within acceptable engineering standards. The sharing ratio consistently exhibits the highest value at the ballast shoulder, followed by the sleeper bottom, with the lowest value observed at the sleeper side. The support stiffness of the sandy ballast bed decreases by 34.56%, which significantly enhances its elasticity. The energy consumption ratio of the sandy ballast bed increases by 9.08%, reducing the direct impact of train loads on the track structure. Furthermore, laying the USP significantly reduces the maximum force chain value within the sandy ballast bed by 33.47%, thereby mitigating stress concentration phenomena. Notably, in the shallow area (0–175 mm), the USP exhibits a markedly vibration-reduction effect. Therefore, it is recommended that the USP be applied in severe sandy ballast bed sections to improve the elasticity of the ballast bed, reduce stress concentration, and diminish vibration effects.