在压缩剪切负荷下,煤石组合体的故障行为
Xiaopeng Li1, Xiangshang Li1, Honghui Yuan2
1Deep Mining and Rockburst Prevention Institute, Chinese Institute of Coal Science, Beijing, China.
Science progress
|January 10, 2024
概括
深层煤炭开采面临的挑战是煤石界面的压缩剪切负荷. 这项研究揭示了在界面裂尖端的明显裂传播标准,这对于理解结构稳定性至关重要.
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:
- 浅层煤炭储量正在耗尽,需要进行深层采矿.
- 深度采矿涉及复杂的应力条件,包括煤石界面的压缩剪切负荷.
- 界面裂对煤岩结构的稳定性产生重大影响.
研究的目的:
- 在压缩剪切负载下,研究岩石和煤类材料接口上的裂传播标准.
- 在故障期间分析预先存在的界面斜裂的行为.
主要方法:
- 单轴压缩实验是在具有先前存在的界面斜裂纹的标本上进行的.
- 一个图像采集系统记录了整个故障过程中的表面斑点场.
- 采用数字图像相关性 (DIC) 来获得应变场和应力强度因子.
主要成果:
- 形成了两个截然不同的菌株定位带,起源于上下裂纹尖端.
- 较低的裂纹尖端早些时候开始断裂,并受到最大周长拉力应力的影响.
- 上层裂纹尖端的启动是由剪切应力主导的,样本最终沿着接口断裂.
结论:
- 应变场的演变准确地反映了裂的产生和传播.
- 不同的骨折标准决定了在上部和下部裂纹尖端的启动.
- 了解这些标准对于确保深层煤矿结构的稳定性至关重要.
关键词:
深层煤炭开采采矿深度煤炭开采采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿深度煤炭采矿压缩 - 剪切组合负荷的压缩-剪切.数字图像关联方法的方法.破裂的界面 破裂的界面 破裂的界面菌株局部化 菌株局部化更多相关视频
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