离散元件分析形状效应对压载体的剪切行为
Wenjie Hou1, Ang Li1, Weimin Song2
1School of Highway, Chang'an University, Xi'an, 710064, Shaanxi, People's Republic of China.
Scientific reports
|September 8, 2023
概括
压载物形状显著影响铁路轨道性能. 这项研究使用离散元件方法来展示尺寸比,球形,圆度和凸度如何影响压载物包装和剪切行为,影响轨道耐用性.
科学领域:
- 地质技术工程 地质技术工程
- 铁路工程 铁路工程是指铁路工程.
- 计算力学 计算力学 计算力学
背景情况:
- 铁路压载层对于运输基础设施至关重要.
- 压载物颗粒形态影响压载物-休眠物相互作用和整体层的耐用性.
研究的目的:
- 研究不同形态参数的铁路压载物的直接切割行为.
- 用离散元件方法分析压载物形状对初始包装状态和剪切性能的影响.
主要方法:
- 产生了四种具有不同的形态参数的压载物类型:面积比 (AR),球状性 (Φ),圆度 (RD) 和凸度 (CON).
- 使用离散元件方法 (DEM) 模拟直接剪切试验.
- 分析了初始包装状态,包括孔隙和正常接触力分布.
- 使用单向ANOVA测试来评估形态参数的意义.
主要成果:
- 最初的多孔性呈现下降,随后随着AR,Φ,RD和CON的上升而增加.
- 这四个形态参数都显著影响了内部摩擦,较大的参数导致摩擦效应较小.
- 一向ANOVA证实了所有参数对初始孔隙和内部摩擦的显著影响.
- 较高的AR和Φ与在剪切过程中较小的协调数相关,归因于压载体形状.
结论:
- 压载物形态是压载物层机械行为的重要因素.
- 这些发现提供了关于优化压载物颗粒形状的见解,以提高铁路轨道的稳定性和耐用性.
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