含水合物沉积物的机械性质和强度标准,考虑到粘土矿物质
Gege Tang1,2, Rui Jia1,2, Huilan He3
1College of Construction Engineering, Jilin University, Changchun 130021, China.
ACS omega
|November 25, 2024
概括
粘土类型对含水沉积物的机械强度和行为产生重大影响. 沉积物中的较高粘土含量增加了应变硬化和剪切收缩,影响了水库的安全性.
科学领域:
- 地质技术工程 地质技术工程
- 海洋地质 海洋地质学
- 能源资源 能源资源
背景情况:
- 粘土含量和类型是影响含水沉积物 (HBS) 机械性能的关键因素.
- 精确评估HBS机械行为对于安全利用天然气水合物储至关重要.
研究的目的:
- 研究粘土类型 (伊利石和蒙莫里隆石) 和含量对HBS的机械性能和强度标准的影响.
- 建立一个预测模型,用于粘土丰富的水合物储库中切割强度.
主要方法:
- 三轴切割试验是在含有不同类型和数量的伊利特和蒙莫里隆岩的含水沉积物上进行的.
- 分析的重点是机械行为,包括应变硬化,体积变形,故障强度,模量,凝聚力和内部摩擦角度.
主要成果:
- 含蒙莫里隆尼特的HBS (M-HBS) 比含伊利特的HBS (I-HBS) 显示出更大的应变硬化和体积变形.
- 应变硬化和剪切收缩都随着粘土含量增加而增加.
- 与M-HBS相比,I-HBS表现出更高的故障强度和模量.
- 在粘土含量和沉积物凝聚力/内部摩擦角度之间发现了明显的线性相关性,受粘土类型的影响.
结论:
- 粘土类型和含量是HBS强度差异和剪切机制的主要驱动因素.
- 一个包含粘土含量的莫尔-库伦强度标准被开发用于预测富含粘土的水合物储库中的剪切强度.
- 这些发现对于确保天然气水合物储开采的安全至关重要.
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