基于热机械合的微裂交叠岩石质量的机械性能研究
Liewang Qiu1, Liangfu Xie1,2,3, Yongjun Qin1,2
1College of Civil Engineering and Architecture, Xinjiang University, Urumqi, China.
PloS one
|February 23, 2024
概括
温度显著影响深层岩石质量的强度,对资源开发构成挑战. 这项研究使用粒子流代码 (PFC2D) 来建模热机械合,揭示了温度如何影响岩石破裂,微裂和在不同软岩石厚度下的应变.
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
- 热机械合器 热机械合器
背景情况:
- 深层岩石质量的机械性能对温度敏感.
- 温度对岩石强度的影响对深度资源开发和工程建设构成挑战.
- 了解热力学行为对于安全高效的地下深层作业至关重要.
研究的目的:
- 为了研究在热负荷下具有微裂纹的岩石质量的单轴压缩反应.
- 分析软岩厚度比 (Hs/H) 对岩石强度,微裂变演变和应变的影响.
- 使用粒子流代码 (PFC2D) 建立热机械合计算模型.
主要方法:
- 在PFC2D中开发热机械合模型.
- 对岩石质量与先前存在的微裂进行单轴压缩试验的模拟,经过温度变化.
- 分析移位,接触力,微裂纹生成和断裂强度作为温度和软岩厚度比的函数.
主要成果:
- 温度诱导的移位和接触力分布模式与软岩厚度比 (Hs/H) 有显著差异.
- 微裂纹的数量通常随着软岩石厚度的增加而减少,与基于Hs/H的垂直应变有明显的关系.
- 失败强度表现出对温度和Hs/H的复杂依赖,显示下降,增加或初始下降,然后增加.
结论:
- 软岩厚度比率极大地影响深层岩层的热力学反应和故障特性.
- 微裂变的演变和应变行为与温度和软岩石的比例密切相关.
- 预测在热负荷下深层岩石质量的行为需要考虑温度,微裂纹特性和地质结构之间的相互作用.
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