循环装载-卸载速度对煤炭单轴机械异构性的影响
Duo Xu1,2, Honghua Song3,4, Like Zhao5
1State Key Laboratory of Water Resource Protection and Utilization in Coal Mining, National Institute of Clean and Low Carbon Energy, Beijing, 102211, China. 475226179@qq.com.
Scientific reports
|November 26, 2025
概括
装卸率显著影响到煤炭的装卸率.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 岩石机械学 岩石机械学
背景情况:
- 了解煤炭的机械异构性对于安全高效的采矿操作至关重要.
- 之前的研究已经探索了影响煤炭机械性能的各种因素,但装载-卸载速度对异性质的具体影响需要进一步研究.
研究的目的:
- 为了研究装载-卸载速度对煤炭单轴机械异构性的影响.
- 分析这些速率如何影响煤炭样本的单轴压力 (UCS),弹性模量和故障特征.
- 在不同的周期性负载条件下,描述微故障机制的异构性和散射能量密度.
主要方法:
- 在煤样本上进行了单轴压缩试验,采用不同异构角的煤样.
- 利用声辐射 (AE) 监测和数字图像相关性 (DIC) 来捕捉微故障和变形.
- 应用了一系列的装载-卸载率来评估它们对机械性能和故障模式的影响.
主要成果:
- 单轴压缩强度 (UCS) 和弹性模量表现出U形异型特征,随着装卸速度的变化而变化.
- 增加加载-卸载速度会降低UCS和轴应变异性,但会增加弹性模量异性.
- 微故障异构和散散能量密度显示出不同的异构模式 (抛物线,波形,U形),取决于负载率和角度.
结论:
- 装卸率是控制煤炭机械异构性和故障行为的关键因素.
- 床铺平面显著影响故障特征,特别是在特定的异形角 (0°,22.5°,45°).
- 较高的装载-卸载率会导致更完整的故障后标本,并提高异型故障特征的可观测性.
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