在非对称负荷下,煤炭和岩石的损害演变特征和构成模型
Tao Wang1,2,3, Hongbao Zhao4, Xiangyang Zhang2
1School of Safety and Emergency Management Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China.
ACS omega
|April 15, 2024
概括
煤岩力学中的不对称负载减少了峰值应力,并改变了故障模式. 增加的不对称负载会导致煤炭和岩石损坏,影响地下挖掘的稳定性.
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
- 采矿工程 采矿工程 采矿工程
背景情况:
- 地下挖掘,如道和道路,由于地质条件和挖掘过程而经历不对称的负载.
- 在这种条件下了解煤岩的机械反应和故障机制对于安全和稳定至关重要.
研究的目的:
- 研究不同程度的不对称负荷对煤岩的机械性能和故障规律的影响.
- 分析不对称负载系数的宏观和微机械效应.
- 为煤炭和岩石在不对称负荷下开发统计损害构成模型.
主要方法:
- 在四种不同的不对称加载模式下对煤岩样本进行了单轴压缩试验.
- 分析了不对称系数对宏观和微机械行为的影响.
- 开发并使用统计损害构成模型来模拟不对称的负载效应.
主要成果:
- 煤岩中的峰应力随着不对称负载系数的增加而线性减少.
- 声辐射环数峰值分布从集中 (均负载) 转移到分散的多相 (不对称负载).
- 不对称的负载诱导应力度,导致剪切故障和裂在加载区接口附近的局部化.
结论:
- 不对称的负载显著改变了煤岩的机械性能和故障特性.
- 已建立的构成模型表明,更高的不对称系数与在同等损伤水平下减少的应变相关.
- 不对称的负载显然促进了煤炭和岩石中的损坏积累,对地下结构完整性构成风险.
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