具有隐藏裂的破碎岩石的机械性能和裂演变特征
Yuxin Ban1, Lihong Chen1, Qiang Xie2,3
1School of Civil Engineering and Architecture, Chongqing University of Science and Technology, Chongqing, 401331, China.
Scientific reports
|July 19, 2023
概括
岩石中隐藏的裂会削弱机械强度,但不如关闭裂. 它们的裂变机制主要涉及拉力失效,与封闭裂纹岩石中混合拉力剪切失效不同.
科学领域:
- 岩石机械 岩石机械 岩石机械
- 地质技术工程地质技术工程
- 材料科学是一种材料科学.
背景情况:
- 关节和空隙等自然缺陷显著影响岩石质量的特性.
- 岩中的隐藏裂对机械性能和裂机制的影响尚不清楚.
研究的目的:
- 为了研究隐藏裂纹岩石样本的机械性能和裂纹行为.
- 为了比较隐藏裂与完整和关闭裂的影响.
主要方法:
- 实验室对预制的隐形裂纹,完整的和闭合裂纹的岩石样本进行测试.
- 同步使用数字图像相关性和声辐射监测以捕捉裂纹过程.
- 分析RA-AF关系以揭示裂纹机制.
主要成果:
- 隐藏的裂降低了单轴压缩强度,但由于内部颗粒凝聚力,它们的削弱效应不如封闭裂那么明显.
- 标本的方向 (α=90°与β=90°) 影响隐藏和关闭裂的启动行为.
- 隐形裂纹样本主要表现出拉力裂纹模式,并补充了剪切,而闭裂样本显示混合拉力剪切故障.
结论:
- 隐藏的裂显著影响岩石的机械特性和断裂模式.
- 了解隐藏裂的独特裂机制对于岩石工程至关重要.
- 这项研究提供了关于具有内部缺陷的岩石行为的见解.
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