在负载下联合煤中的声波发射和微裂纹的演变及其相关性
Zhiming Wang1,2,3, Kun Guan3, Zhenhua Li1
1Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization, Henan Polytechnic University, Jiaozuo, Henan 454003, China.
ACS omega
|November 29, 2023
概括
这项研究揭示了联合煤在压力下如何破裂,确定剪切和张力是关键的损伤类型. 它开发了一种计算煤炭多孔性和连接性的方法,有助于预测地下矿山的稳定性.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 材料科学 材料科学 材料科学
背景情况:
- 预测压缩下联合煤的稳定性对于地下采矿安全至关重要.
- 了解持续的损伤和裂过程对于准确的稳定性预测至关重要.
研究的目的:
- 为了研究在单轴压缩下结合煤的损伤和裂纹过程.
- 分析声辐射 (AE) 信号与内部断裂参数之间的相关性.
- 开发一种计算煤炭多孔性和连接性的方法.
主要方法:
- 单轴压缩试验,用于带有不同床位平面方向的联合煤样品.
- 声波排放 (AE) 监测以检测微碎事件.
- 计算机断层扫描 (CT) 扫描以可视化内部骨折的发展.
- 对AE信号 (D1) 和断裂 (D2) 的碎形维度分析.
主要成果:
- 分别在A和B样本中,剪切和张力裂被确定为主要的损伤机制.
- 在应力峰值之前,在AE计数碎形维度 (D1) 中观察到一个明显的下降谷,在样本A中更宽.
- 断裂碎片尺寸 (D2) 在产量和高峰后阶段显著增加,在样本A中具有更高的值.
- 累积D1 (AD1) 和D2之间建立了一个单调的关系,使透性和连接性计算成为可能.
结论:
- 该研究提供了基于床层平面方向的联合煤的独特故障模式的见解.
- 开发的方法允许定量评估压缩合煤的孔隙性和连接性.
- 这些发现有助于更好地预测煤炭的稳定性以及地下矿山中水和气体流通道的变化.
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