关于煤炭在分级循环装载和卸载应力路径下的故障和声学排放特征的研究
Minke Duan1,2, Meijuan Lu1, Ruiqi Ban1
1Anhui Engineering Research Center of Exploitation and Utilization of Closed/Abandoned Mine Resources, Anhui University of Science and Technology, Huainan, Anhui, 232001, China.
Scientific reports
|November 6, 2024
概括
循环压力显著影响煤炭的机械行为. 声波排放 (AE) 分析揭示了装载和卸载过程中不同的模式,这对于预测采矿灾害至关重要.
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
- 材料科学 材料科学 材料科学
背景情况:
- 煤炭开采容易受到周期性压力带来的干扰.
- 了解煤炭在压力下的机械反应对于安全至关重要.
- 声波发射 (AE) 是监测物质损坏的一个关键技术.
研究的目的:
- 研究周期性干扰应力对煤炭机械行为的影响.
- 在分级循环装载和卸载过程中分析声辐射 (AE) 特性.
- 评估AE信号划分区域,并量化循环应力下的凯泽效应.
主要方法:
- 使用含有气体的煤炭流体-固体合伺服透实验系统.
- 应用分级循环装载和卸载应力路径.
- 分析了AE信号特征,包括AE计数,累积声,凯泽效应,费利西蒂效应和AE参数 (AF,RA).
主要成果:
- 在装载和卸载路径上,AE信号的特征是相似的.
- 在故障时AE数量达到峰值,累积AE数量呈指数增长.
- 在AE信号中的明确区域划分显示了Kaiser效应在低/中等压力区域和Felicity效应在高压力区域.
- 新定义的系数量化了凯泽效应,显示了随着应力变化增加的下降趋势.
- 煤炭故障主要是拉伸性,在循环卸载期间有更多的拉伸性故障信号.
结论:
- AE信号分析提供了关于在循环应力下煤炭机械行为的见解.
- 凯泽和费利西蒂效应在循环负荷下的煤炭中是可观察和量化的.
- 定义的AE系数为特征压力效应提供了一种新的方法.
- 这些发现对预测和减轻采矿业务中煤炭发电灾害具有重要意义.
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