在冰解周期下,砂岩的强度降解特征和损伤构成模型
Zhongwen Wang1,2, Meilu Yu3,4, Lei Wang1
1State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, Anhui University of Science and Technology, Huainan, 232001, Anhui, China.
Scientific reports
|September 30, 2024
概括
调查青海-西高原的冰岩损伤表明,融周期会增加岩石的多孔性,削弱机械强度. 一个新的构成模型准确地预测了这种对基础设施发展至关重要的损害.
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
- 环境科学 环境科学
背景情况:
- 青海-西高原等高海拔和寒冷地区面临着独特的挑战,因为冰岩石的动态.
- 了解这些动态对于基础设施,生态保护和可持续发展至关重要.
研究的目的:
- 为了研究冷-解周期下的冰岩损伤的规律.
- 分析冷解周期对岩石多孔性和机械性能的影响.
- 为冰融化岩石开发一个合损害构成模型.
主要方法:
- 岩石样本经过冷解周期 (-20°C至20°C),模拟高原条件.
- 使用MTS816系统进行了单轴压缩测试.
- 核磁共振分析 (MesoMR12-060 H-I) 量化了多孔性的变化.
- 使用莱梅特等效菌株理论得出了一个构成模型.
主要成果:
- 结会导致冰升高,孔隙扩大并引发裂;解导致水迁移到新的微孔.
- 微观层面的多孔性增加显著削弱了宏观层面的岩石机械参数.
- 衍生出的细分结解损害构成模型有效地与实验数据相匹配.
结论:
- 结解周期通过改变孔隙结构和降低机械强度来降低岩石完整性.
- 开发的构成模型为预测寒冷环境中的岩石损伤提供了可靠的工具.
- 这些发现支持在青海-西高原改善基础设施设计和环境管理.
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