关于煤炭变形和故障特征的演变规则的研究,由多次采矿干扰引起的
Yang Liu1, Zhenhua Ouyang2,3, Chunlei Li4
1School of Mechanics and Engineering, Liaoning Technical University, Fuxin, 123000, China.
Scientific reports
|October 25, 2024
概括
多重采矿干扰 (MMD) 导致煤炭变形和损坏. 了解循环加载和冲击下的煤炭行为有助于防止像岩石爆裂这样的采矿灾害.
科学领域:
- 地质技术工程 地质技术工程
- 采矿工程 采矿工程 采矿工程
- 岩石机械学 岩石机械学
背景情况:
- 煤矿开采活动容易受到多次采矿干扰 (MMD) 的影响.
- 这些干扰可以导致煤炭变形,损坏和灾难性事件,如岩石爆裂.
- 了解煤炭对这些压力的反应对于预防灾害至关重要.
研究的目的:
- 为了研究煤炭在多重采矿干扰 (MMD) 下的变形演变和断裂特征.
- 在近静态循环加载-卸载 (L-U) 和动态轴向压缩下分析煤炭行为.
- 为减轻采矿引发的灾害提供理论基础.
主要方法:
- 在大型煤样样本上进行了准静态单轴循环加载-卸载 (L-U) 试验.
- 在损坏的煤样品上进行了动态轴向压缩测试.
- 采用3D激光扫描和声辐射 (AE) 监测用于数据采集.
主要成果:
- 循环的L-U加载导致煤样中的"波状"变形趋势.
- 最大负载是影响煤炭变形的主要因素;较低的负载导致变形较少.
- 冲击动态负荷造成了大规模的分裂故障,压力剪切故障发生在内部孔内.
- 较低的循环负荷与减少损坏和较小的碎片颗粒 (更高的碎片尺寸) 在撞击失效时相关.
- 从内部孔向外延伸的裂随着L-U周期,负载和周期数量的增加,表明损伤更严重.
结论:
- 该研究阐明了在MMD下煤炭变形和故障模式.
- 加强路面和尽量减少低负载周期性干扰是重要的实际考虑.
- 这些发现为加强采矿灾害预防和控制策略提供了理论基础.
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