围绕岩石的机械行为和裂演变,不同的屋顶接触填充率
Jie Wang1,2, Kaifei Huang1,2, Jianxin Fu1,2
1School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
在矿中增加屋顶接触填充率 (RCFR) 会提高周围岩石的稳定性和机械性能. 更高的RCFR提高了峰值应力和弹性模量,这对于更安全的采矿操作至关重要.
科学领域:
- 采矿工程 采矿工程 采矿工程
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
背景情况:
- 采矿区的填充对于改善周围岩石的稳定性至关重要.
- 屋顶接触填充率 (RCFR) 显著影响围绕岩石 (GSR) 的稳定性.
- 了解RCFR对机械性能和裂传播的影响对于矿山安全至关重要.
研究的目的:
- 调查屋顶接触填充率 (RCFR) 对围绕岩石 (GSR) 的机械特性和裂传播的影响.
- 分析不同的RCFR和goaf大小如何影响GSR的峰值应力,峰值应变和弹性模量.
- 在不同的填充条件下,描述GSR内部的裂纹启动,传播和故障机制.
主要方法:
- 在GSR样本上进行双轴压缩实验.
- 在各种操作条件下进行数值模拟实验.
- 分析了声音排放的响声计数,以监测裂的发展.
主要成果:
- GSR峰值应力,峰值应变和弹性模量随着RCFR的增加而增加,随着goaf的大小而减少.
- 裂的传播呈现出不同的阶段:缓慢启动,快速扩张和宏观断裂形成.
- 剪切裂在岩石中占主导地位,拉伸裂在回填,在岩石中传播更快.
结论:
- RCFR是控制GSR稳定性和机械行为的关键因素.
- 应力度是GSR失效的主要驱动因素,在岩石和填充中具有不同的应力倍数.
- 优化RCFR可以提高矿山安全和周围岩石的完整性.
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