关于在异常负荷下具有孔缺陷的煤样品的半机械行为和损伤过程的研究
1School of Vehicle and Transportation Engineering, Taiyuan University of Science and Technology, Taiyuan, China.
PloS one
|May 2, 2024
概括
异常负荷显著影响煤柱稳定性,减少峰值应力和裂的发生. 相对于负载区域的缺陷位置决定了采矿过程中的宏观裂模式.
科学领域:
- 采矿工程 采矿工程 采矿工程
- 岩石机械学 岩石机械学
- 地质技术工程 地质技术工程
背景情况:
- 在资源回收过程中,煤柱稳定性对于覆盖岩石斜坡的完整性至关重要.
- 异常负荷,由于覆盖的岩石重量,影响煤柱的设计和稳定性.
- 了解在异常负荷下裂演变对于安全的采矿实践至关重要.
研究的目的:
- 为了研究异常负荷对具有孔缺陷的煤样品的影响.
- 分析负载离心率与煤炭机械性能之间的关系.
- 为了描述在异常压缩下裂启动和传播的阶段.
主要方法:
- 使用PFC离散元件软件进行数值模拟.
- 对煤样品进行了单轴压缩试验,其中孔缺陷位置不同.
- 校准了微机械参数以模拟现实的煤炭行为.
主要成果:
- 峰值应力,裂纹应力和扩张应力随着负载偏心率的增加线性下降.
- 微裂变进化表现出四个不同的阶段:启动,稳定传播,不稳定传播和后失败.
- 宏观裂分布受到孔缺陷位置和装载面积之间的相互作用的影响.
结论:
- 负载偏心显著削弱了煤样,压力降低遵循线性趋势.
- 孔缺陷的存在和位置极大地影响了在异常负荷下裂传播模式.
- 采矿设计必须考虑到异常负荷和缺陷位置,以确保煤柱的稳定性.
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