用Al3+,Fe3+和Si4+改性水泥材料稳定软土壤:比较,模拟和稳定机制
Haoming Wang1, Yongjie Ding1, Guohua Ren1
1School of City and Transportation, Beijing University of Technology, Beijing 100124, China.
The Science of the total environment
|June 18, 2025
概括
这项研究揭示了固体废物改性水泥中的铁 (Fe3+) 和 (Al3+) 离子如何改善软粘土土壤的稳定性. 这些离子减少孔径,增强结构完整性,提供有效的土壤稳定解决方案.
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:
- 软粘土土壤由于剪切强度低和压缩能力高,因此存在工程挑战.
- 了解固体废物修改中的水泥稳定机制对于有效改善土壤至关重要.
研究的目的:
- 在软粘土土壤中研究固体废物改性水泥的离子级稳定机制.
- 探索特定离子 (Fe3+,Al3+) 在增强土壤特性中的作用.
主要方法:
- 开发了四种固体废物改性水泥配方.
- 压力强度的分析,毛孔大小的分布,和多孔性.
- 福里埃变换红外光谱 (FTIR) 用于键形成分析.
- 对于离子相互作用的随机移位 (RDF) 和分子动力学 (MSD) 模拟.
- 用能量分散光谱扫描电子显微镜 (SEM-EDS) 检测材料组成.
主要成果:
- 用Al3+修饰的水泥处理实现了高达15MPa的压力强度.
- 毛孔大小减少到4-5nm,表明毛孔性降低.
- FTIR证实了FeO和AlO的债券形成.
- RDF和MSD模拟显示了降低的泽塔潜力和扩散的双层厚度,促进花.
- SEM-EDS揭示了由促进的均水化和凝阶段形成,而抑制了晶体的结晶.
- 在Fe3+和Al3+修改系统中,相互作用能量低至22,000kJ/mol.
结论:
- 适度至高度的Al3+和Fe3+对于最佳的软粘土土壤稳定至关重要.
- 离子相互作用,包括降低的泽塔潜力和扩散的双层厚度,是关键机制.
- 固体废物改性水泥为缓解粘土土壤缺陷提供了强大的解决方案.
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