在单轴压缩条件下,不同岩石的声辐射特性和损伤演变
Jianchun Ou1, Enyuan Wang2, Xinyu Wang3
1State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, China.
Scientific reports
|February 20, 2024
概括
了解岩石断裂是安全深层煤矿开采的关键. 声辐射 (AE) 分析显示,脆性岩石显示出较少的故障前能量消散和较少明显的AE前体,RA-AF值标志着故障模式.
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
- 材料科学 材料科学 材料科学
背景情况:
- 深层煤炭开采在监测和识别由于复杂的岩层而导致的岩石裂变灾害方面面临着挑战.
- 确保煤炭开采的安全性和可持续性,需要对岩石破裂机制有充分的了解.
研究的目的:
- 在单轴压缩下研究不同类型岩石的机械性能,能量演变和声辐射 (AE) 特性.
- 分析AE反应与岩石损伤/断裂过程之间的关系.
- 开发和验证基于AE和消散能量的损害模型.
主要方法:
- 在四种岩石类型上进行了单轴压缩测试:黄色砂岩,白砂岩,大理石和石灰岩.
- 在测试期间,同时进行声辐射 (AE) 监测.
- 分析了机械性能,能量演变和AE特征.
- 使用AE能量和分散能量开发了损害模型.
主要成果:
- AE反应与岩石的损伤和断裂过程密切相关.
- 更易碎的岩石表现出更少的能量消散和更不明显的AE前体在故障之前.
- RA-AF值有效地描述了不同岩石的故障模式.
- 基于散散能量的损伤模型准确地反映了岩石的应力和损伤状态.
结论:
- 该研究提供了有关深层煤矿开采相关的各种岩石故障机制和AE特征的见解.
- 基于分散能量的损伤模型提供了一种可靠的方法来评估岩石应力和损伤.
- AE监测,特别是RA-AF分析,对于理解和预测岩石断裂至关重要.
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