关于非穿透裂空间分布对脆性骨折过程的影响的实验研究
Jun Xu1, Sen Luo1, Xiaochun Xiao2
1School of Mechanics and Engineering, Liaoning Technical University, Fuxin, 123000, China.
Scientific reports
|August 1, 2024
概括
石膏样本中不可穿透的裂的倾斜程度显著影响岩石强度和断裂模式. 了解这些裂纹行为对于推进岩石裂纹和3D裂纹理论至关重要.
科学领域:
- 岩石机械学 岩石机械学
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 岩石断裂是一个复杂的过程,受到先前存在的缺陷的影响.
- 非穿透裂是常见的地质不连续性,影响岩石质量的行为.
- 了解裂相互作用和传播对于预测岩石质量稳定性至关重要.
研究的目的:
- 为了研究非穿透裂对岩石裂的空间分布和影响.
- 分析裂纹前倾斜对石膏样本机械强度的影响.
- 在单轴压缩下描述裂纹模式和裂纹传播.
主要方法:
- 在立方石膏样本 (100mm x 100mm x 100mm) 上进行单轴压缩试验.
- 包括两条直角不穿透的裂,深度和倾斜度各不相同.
- 从 0°到 150°,系统地调整主要的裂纹前倾斜角度.
主要成果:
- 样品强度最初随着裂纹前倾斜而增加,达到90°的峰值,然后下降.
- 拉伸裂纹百分比随着倾斜而变化,与强度波动相关.
- 不透的裂引发了表面分裂,反翼裂,并影响了邻近的裂传播.
结论:
- 非穿透裂的空间分布和倾斜程度极大地影响岩石强度和断裂行为.
- 断裂表面表现出混合模式特征 (表面上的I-III,内部的I-II-III).
- 这些发现有助于更深入地了解岩石断裂过程和3D断裂力学.
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