通过碳酸改性红色粘土的微观孔隙和物理机械性能研究
Lijie Chen1,2,3, Xiao Wang1, Qingyang Deng1
1Key Laboratory of Disaster Prevention & Mitigation and Prestress Technology of Guangxi Colleges and Universities, Guangxi University of Science and Technology, Liuzhou, 545006, China.
Scientific reports
|October 11, 2024
概括
用碳酸修改的红色粘土显示出改进的性能,包括减少液态塑料限值和收缩. 这项研究详细介绍了对土壤结构的影响,并为预测其在工程应用中的行为提供了一个更正的模型.
科学领域:
- 地质技术工程 地质技术工程
- 土壤科学 土壤科学
- 材料科学 材料科学 材料科学
背景情况:
- 红色粘土表现出有问题的高液态塑料极限,水膨胀和收缩.
- 这些特性限制了其在建筑和基础设施项目中的使用.
- 修改红色粘土是必要的,以改善其工程特性.
研究的目的:
- 为了研究碳酸修饰对红色粘土特性的影响.
- 分析不同碳酸含量对土壤结构和机械行为的影响.
- 开发和验证一个用于修改红色粘土性能的预测模型.
主要方法:
- 使用来自广西赫州的碳酸进行土壤修改.
- 测试包括液体塑料极限,收缩,核磁共振 (NMR),X射线衍射 (XRD),扫描电子显微镜 (SEM) 和整合排水 (CD) 三轴切割测试.
- 采用了肯-张模型,并随后进行了修正,以提高预测准确度.
主要成果:
- 最佳碳酸含量 (20%) 显著降低了液态塑料限值和收缩系数.
- 蒙莫里隆石含量下降,表明结构变化.
- 核磁共振揭示了毛孔大小分布的变化,含碳酸含量各不相同,而毛孔性通常增加.
- 一个经过校正的肯-张模型准确地预测了三轴切割试验中的应力-应变行为.
结论:
- 碳酸的修改有效地改善了红色粘土的工程性能.
- 该研究提供了对微观结构变化及其对宏观行为的影响的见解.
- 修正后的预测模型为修改红色粘土的实际应用提供了可靠的理论基础.
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