岩石样本在循环低能倾斜撞击平面下的累积损伤特征
Xinrong Wang1, Xu Zou2, Zeng-Xiang Lu3
1School of Mining Engineering, University of Science and Technology Liaoning, Anshan, 114051, China.
Scientific reports
|October 28, 2024
概括
矿石冲击对岩石造成的损伤在较高的冲击角度减少,45°导致最严重的故障. 循环冲击最初关闭毛孔,然后扩大它们,导致岩石退化和裂形成.
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
- 采矿工程 采矿工程 采矿工程
背景情况:
- 在地下矿山中,矿石通道因矿石冲击和磨损而受损.
- 了解撞击下的岩石断裂机制对于矿石通道的设计和维护至关重要.
研究的目的:
- 在周期性低能量冲击下,以各种倾斜角度调查岩石损伤和故障机制.
- 用核磁共振 (NMR) 分析孔隙变化和裂纹形成.
主要方法:
- 循环低能冲击测试在砂岩上使用倾斜冲击装置和落.
- 通过核磁共振 (NMR) 检测系统进行孔径测量和分析.
- 评估T2频谱分布和撞击后的NMR成像.
主要成果:
- 倾斜角度增加通常会减少岩石损伤,45°显示最严重的损伤.
- 孔隙性随着撞击周期而波动:减少,然后增加,然后减少.
- 新的裂形成,现有的裂扩大;宏孔主导样本降解.
结论:
- 撞击角度显著影响岩石损伤,在较高的角度普遍存在剪切拉伸故障.
- 孔隙结构的演变 (关闭然后扩张) 决定了循环负荷下的岩石退化.
- 尽管发生了微孔变化,但巨孔特征仍然对岩石破裂至关重要.
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