单轴压缩故障特征和不同应变速率下的破碎煤质量的构成模型
Zihao Feng1, Haitao Li1, Xiaoshan Shi1
1Deep Mining and Rock Burst Research Institute, Chinese Institute of Coal Science, Beijing 100013, China.
Materials (Basel, Switzerland)
|May 14, 2025
概括
这项研究揭示了应变速率和断裂密度如何影响煤炭的机械性能. 较高的拉伸率增加了压力强度,而更多的断裂降低了压力强度,影响了煤炭的结构完整性.
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:
- 了解煤炭在不同条件下的机械行为对于安全的采矿和资源开采至关重要.
- 断裂密度和应变率显著影响岩石材料的强度和变形.
- 现有的模型可能无法完全捕捉破碎煤中这些因素之间的复杂相互作用.
研究的目的:
- 研究不同应变速率和断裂密度对煤炭机械行为的影响.
- 建立和完善破碎煤的统计损害构成模型.
- 在动态负载下分析煤炭碎片的碎形特征.
主要方法:
- 计算机断层扫描 (CT) 扫描用于量化煤样中的断裂含量.
- 单轴压缩试验用于分析各种应变速率下的机械特性.
- 开发和修改一个包含韦布尔分布参数的统计损害构成模型.
主要成果:
- 压力强度与拉伸率正相关,与断裂密度负相关.
- 弹性模块对断裂密度敏感,特别是在较低的拉伸速率下.
- 碎片尺寸和碎片质量随着变化速率的增加而增加,这表明粒子大小的不均性更大.
- 韦布尔参数 (F0,m) 在临界应变率 (0.01s−1) 和断裂密度 (0.3%-0.45%) 值周围显示出明显的趋势.
结论:
- 应变速率和断裂密度是控制煤炭机械反应的关键参数.
- 修改后的统计损害构成模型提供了更准确的断裂煤行为表示.
- 应变速率和断裂密度的值显著改变了材料的损伤演变和碎片化模式.
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