破裂行为和压力场进化在煤样本含有床铺在单轴压缩下的煤炭样本
Chang Guo1,2, Zedong Wang1, Ting Liu2
1College of Quality and Safety Engineering, China Jiliang University, Hangzhou 310018, China.
ACS omega
|October 16, 2023
概括
这项研究揭示了床铺倾斜角度如何影响煤炭强度和变形. 了解这些结构性异构性对于更安全的地下采矿和防止天然气灾害至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 计算建模 计算建模
背景情况:
- 地下采矿遇到的煤层具有不同的床层结构.
- 底层结构显著影响煤层强度,变形和与气体有关的危险.
- 有限的数据存在于煤炭的机械性能与床层诱导的结构异构性.
研究的目的:
- 为了研究具有床结构的煤样本的机械性能.
- 分析不同床倾斜角度对煤炭行为的影响.
- 为了理解裂传播和压力场在异型煤中的演变.
主要方法:
- 使用粒子流代码 (PFC) 方法进行数值建模.
- 模拟不同倾斜角度的煤矿样本.
- 实验室测试用于验证数值结果.
主要成果:
- 床铺倾斜角度显著影响机械性能和裂纹图案.
- 在加载过程中分析应力场的时间和空间演变.
- 根据布置角度确定了三种不同的裂纹启动模式.
- 机械性能与碎形维度之间建立的定量关系.
结论:
- 数字模拟为煤炭的异型机械行为提供了宝贵的见解.
- 这些发现有助于更好地理解煤层对应力和变形的反应.
- 结果有助于改进天然气开采和防灾战略在地下采矿.
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