在粒度水平上进行数值模拟,以测量薄硬质砂岩的有效弹性
1Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China.
ACS omega
|September 25, 2023
概括
这项研究使用离散元素方法 (DEM) 来建模软化的砂岩,揭示了它们的机械行为取决于粒际水泥特性. 这些发现与实验数据一致,并突出了硬粒聚合物的应力度.
科学领域:
- 地质技术工程 地质技术工程
- 计算力学 计算力学 计算力学
- 材料科学 材料科学 材料科学
背景情况:
- 薄弱凝固的砂石表现出松散的颗粒间接触,高孔隙性和显著的粘土含量.
- 了解这些岩石的有效弹性至关重要,特别是粒度接触时的凝固行为.
研究的目的:
- 通过使用离散元素方法 (DEM) 数字地研究弱凝固的砂岩的有效弹性.
- 分析水泥形态和成分对砂岩机械性能的影响.
主要方法:
- 开发了一个离散元素方法 (DEM) 方案,使用正常和剪切弹来建模晶体间水泥的行为.
- 对于有限尺寸的水泥,定义了三个形态参数 (水泥厚度,粘合半径,粒径).
- 为接触结合和远距离结合模式创建了数值模型,以及具有不同石英和粘土比例的人工砂岩样本.
主要成果:
- 在特定条件下 (小接触宽度/厚度,大模块),DEM模拟与理论预测的有效弹性,特别是剪切模块的良好一致.
- 人工砂岩样本的模拟与超声波测量密切匹配,验证了各种石英粘土混合物和松散压缩的模型.
- 微机械分析显示,在软化的砂岩中,强大的机械行为集中在硬粒的凝聚性聚合物中.
结论:
- DEM方法有效地捕捉了薄弱水泥化的砂岩的机械行为,将宏观性质与微观水泥特性联系起来.
- 该研究提供了关于水泥形态和成分在确定砂岩有效弹性和故障机制中的作用的见解.
- 研究结果证实,硬粒聚合物中的应力局部化显著影响了这些地质材料的整体强度.
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