在动态静态合负载下对多向受约束的含水煤样品的动态机械性能进行实验研究
Beijing Xie1, Ben Zhang2, Shunkun Zhao3
1School of Emergency Management and Safety Engineering, China University of Mining and Technology, Beijing, 100083, China.
Scientific reports
|September 4, 2024
概括
深水会影响煤炭的机械性能. 和煤在低应变率下表现出较低的强度,但在高应变率下表现出较高的强度,这是由于水的影响.
科学领域:
- 地质技术工程 地质技术工程
- 岩石力学 岩石力学 岩石力学
- 材料科学 材料科学 材料科学
背景情况:
- 在深水下了解煤炭和岩石的行为对于安全的采矿和地下施工至关重要.
- 动态机械性能是预测冲击负载下故障的关键.
研究的目的:
- 研究深水条件下煤炭的动态机械性能.
- 分析含水量对煤炭强度,能量消耗和碎形尺寸的影响.
主要方法:
- 用一个增强的SHPB测试系统进行动态冲击实验.
- 在不同含水量和加载条件的煤样本上进行了五组实验.
- 采用HJC模型和ANSYS/LS-DYNA进行煤炭故障的数值模拟.
主要成果:
- 与天然煤相比,和煤在低应变率下表现出较低的动力强度,但在高应变率下表现出更高的峰值强度.
- 和煤的能量吸收率降低了10-30%,在天然煤中观察到变形歇斯底里.
- 在混合负荷下,和煤中的碎形尺寸和细颗粒含量增加.
结论:
- 水含量显著改变了煤炭的动态机械特性和故障机制.
- 数字模拟充分证实了实验结果,验证了HJC模型用于预测煤炭故障.
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