在冷解周期下,面部骨折的土的恶化机制
Runsen Lai1, Zizhao Zhang2,3, Jianhua Zhu4
1College of Geology and Mining Engineering, Xinjiang University, Urumqi, 830017, China.
Scientific reports
|June 11, 2024
概括
结冰解周期会降低岩石质量的强度和波速,特别是在破碎的岩石中. 这项研究揭示了融损伤如何影响寒冷地区的岩石力学和断裂形态.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 寒冷地区工程 寒冷地区工程
背景情况:
- 表面裂显著影响岩石质量机制,是岩石质量破坏的主要原因.
- 结冰解周期对寒冷环境中岩石质量的完整性构成重大挑战.
- 了解破碎岩石中融损伤对于在寒冷地区的工程安全至关重要.
研究的目的:
- 研究冷解周期对带有预制表面接头的的机械性质和断裂形态的影响.
- 分析受融条件下的岩石样本中的质量损失,波速变化和微观结构变化.
- 为了阐明结融化周期对岩石强度随时间的推移而减弱的影响背后的机制.
主要方法:
- 实验室冷解循环测试对图夫样本进行,包括对照组和预制合组.
- 进行了单轴压缩试验,以评估冷解暴露后样本的机械性能.
- 使用扫描电子显微镜 (SEM) 检查宏观和微观宇宙骨折损伤形态.
主要成果:
- 观察到质量,波速和单轴压力强度的持续下降,冷-解周期的数量越来越多.
- 与对照组相比,预制的联合样本表现出更明显的降解.
- SEM分析显示了粒子碎片化和从表面凝固到接触点的转移,削弱了岩石的压力强度.
结论:
- 结冰解周期显著降低了破碎岩石质量的机械性能,现有的关节加剧了损伤.
- 微观结构的变化,包括粒子分解和改变的接触点,是强度降低的关键机制.
- 这些发现为工程实践和寒冷地区的风险评估提供了宝贵的见解.
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