在限制压力下的煤炭故障中,裂传播和AE前体特征的数值模拟
Gang Jing1,2,3,4, Shuai Wang5,6,7,8, Leilei Zhao5,6,7,8
1Key Laboratory of Xinjiang Coal Resources Green Mining, Xinjiang Institute of Engineering, Ministry of Education, Ürümqi, 830023, China. gang.jing.chn@foxmail.com.
Scientific reports
|July 2, 2025
概括
这项研究揭示了限制压力如何影响煤炭裂传播和声辐射 (AE) 信号,这对于预测深矿煤炭爆发至关重要. 了解这些AE特征可以通过提高煤炭爆预测准确度来提高安全性.
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
- 采矿工程 采矿工程 采矿工程
背景情况:
- 煤炭爆发在深层采矿操作中构成重大风险.
- 了解裂传播和声学辐射 (AE) 对于预测这些事件至关重要.
- 三轴应力条件是深地下环境的代表.
研究的目的:
- 通过使用离散元件模拟来研究在不同限制压力下煤的机械行为和AE反应.
- 阐明限制压力对裂演变和煤炭爆发AE前体指标的影响.
主要方法:
- 使用离散元件模拟 (DEM) 来建模圆柱形煤样本.
- 模拟在不同的限制压力和加载速度下进行.
- 分析的重点是峰值强度,体积应变应变曲线,裂纹比例和AE参数 (βt值和b值).
主要成果:
- 峰值强度随着负载率的增加而增加,在更高的限制压力下,灵敏度降低.
- 封闭压力提高了裂启动/损伤值,并缩短了不稳定的裂传播时间.
- 拉伸裂纹比例减少,而剪切和混合模式裂纹随着限制压力而增加.
- βt值表示稳定性 (<1) 或不稳定性 (>1) 并不受限制压力的影响.
- 在失败之前,b值表现出一个特有的"急剧下降高原"模式.
结论:
- 限制压力显著影响煤的机械反应和AE特性.
- 像βt值和b值这样的AE参数可以作为预测煤爆的可靠指标.
- 这些发现为在深度采矿中解释AE信号提供了理论基础,以提高安全性.
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