煤石介质的内部应力转移特征在基于粒子流量方法的集中力下
Yongping Wu1,2,3, Yepeng Tang4,5,6, Panshi Xie1,2,3
1College of Energy Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China.
Scientific reports
|March 8, 2024
概括
了解煤岩中的内部应力转移对于采矿安全至关重要. 本研究使用数值模型揭示压力如何通过不同的煤和岩石组合移动,识别关键接口效应和压力度区域.
科学领域:
- 地质技术工程 地质技术工程
- 岩石力学 岩石力学 岩石力学
- 采矿工程 采矿工程 采矿工程
背景情况:
- 可观测到煤岩的宏观变形和失效,但内部应力转移机制尚不清楚.
- 了解压力转移对于预测采矿引起的地质危险至关重要.
研究的目的:
- 为了研究内部应力转移规律和分布特征在煤岩介质在集中负荷下.
- 分析石质学和组合方法对应力转移路径的影响.
主要方法:
- 使用了离散元件方法 (DEM).
- 使用PFC2D软件创建了纯煤/岩石和煤岩组合样本的数值模型.
- 分析的重点是宏观应力和中观力链.
主要成果:
- 应力转移主要遵循"点源辐射"模式,在煤和岩石之间观察到接口效应.
- 纯样本中的石质学差异改变了应力值和局部方向,而不是整体模式.
- 接口处较大的石质对比度会放大接口效应,特别是当应力从强岩石转移到弱煤时.
结论:
- 在煤石组合中,界面效应是显著的,特别是在不同强度的煤石组合中.
- 压力波浪集中在靠近接口的高强度岩石中.
- 这些发现为了解采矿诱导的机械行为和煤柱下的地板稳定性提供了理论基础.
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