关于具有不同应力负荷和卸载条件的复合样本的声学辐射的动态多分体特征
Yuben Liu1,2, Xiangxi Meng3,4
1College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, 266590, China.
Scientific reports
|March 30, 2024
概括
在模拟的采矿深度下调查复合层故障显示,更深的采矿会造成较少的损坏,拉力剪切故障. 声波排放的多分法分析量化不稳定性,对于预测煤矿灾害至关重要.
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:
- 复合层结构在中国西部很常见,可能会阻碍稳定性和煤矿动态灾害.
- 了解不同压力条件下的故障特征对于安全和预测至关重要.
研究的目的:
- 分析三轴加载和卸载对复合岩石样本不稳定性的影响.
- 评估模拟的采矿深度如何影响样本承载能力,声辐射 (AE) 参数和多分形特征.
主要方法:
- 三个三轴加载和卸载测试方案旨在模拟不同的现场采矿深度.
- 对12组复合样本组进行了复杂的三轴测试.
- 分析包括轴承能力,AE参数和声波发射时间序列的动态多分体特征.
主要成果:
- 模拟更深的采矿深度的样本显示损伤较小,拉力剪切混合故障模式,拉力故障占主导地位.
- 声辐射多分体参数 (q和Dq) 显示与采矿深度相关的趋势,Dq随深度而下降,q随深度而增加.
- 四层复合样本比三层样本显示的多分体参数变化较小,表明后者更复杂的微裂传播和更高的损伤.
结论:
- 采矿深度显著影响复合层的故障模式和不稳定性.
- 声波辐射多分体分析提供了一种定量方法,用于评估岩石质量损害和预测动态灾害.
- 微裂纹传播的复杂性,受样本结构和应力条件的影响,是理解复合层故障的关键.
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