用于分析岩石材料中的多种故障机制的逐步线性强度模型.
Shiqi Li1, Yuan Li1, Dongjue Fan1
1School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel, Switzerland)
|August 29, 2024
概括
岩石故障涉及诸如断裂和剪切等多种机制. 这项研究引入了一种新的零碎线性模型来分析这些复杂的岩石强度行为,改善故障预测.
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
- 材料科学 材料科学 材料科学
背景情况:
- 岩石材料的故障表现出共同存在的机制 (破裂,剪切,压缩).
- 在宏观上,这些表现为多个故障模式和非线性强度特征.
- 现有的岩石力学理论往往侧重于单个故障机制,限制了它们的适用性.
研究的目的:
- 评估岩石表现出多个故障机制的替代强度理论.
- 为分析多机制岩石断裂提出一种新的断片线性强度模型.
- 揭示多机制岩石材料故障背后的内在机制.
主要方法:
- 基于延伸-应变标准和保罗-莫尔-库伦 (PMC) 模型开发了一种断片线性强度模型.
- 构建一个多重失效机制强度模型,使用与一般化剪切应力,平均应力和应力Lode角度的不等式.
- 在各种应力条件下对砂岩和花岩样本进行强度测试.
主要成果:
- 在不同应力条件下的砂岩和花岩中观察到明显的断片线性强度特征.
- 验证了拟议的多重故障机制模型的合理性和适用性.
- 证明了该模型适用于分析复杂的岩石断裂行为.
结论:
- 已成功构建了用于岩石的多机制故障模型.
- 拟议的模型增强了岩石结构故障的预测能力.
- 这些发现有助于理解和预防与岩石相关的结构性故障.
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