阳离子乳化剂和乳化青对水合和水泥微观结构的影响
Panpan Zhang1,2, Yitong Hou2, Kaimin Niu1,2
1Research Institute of Highway, Ministry of Transport, 8 Xitucheng Road, Haidian District, Beijing 100088, China.
Materials (Basel, Switzerland)
|January 11, 2024
概括
阳离子乳化剂和青显著延迟水泥的水化,并改变微观结构. 缓定离子乳化青显示出最明显的效果,增加了固时间和水泥糊中的孔径大小.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 建筑材料 建筑材料
背景情况:
- 由于其刚性和性,水泥乳化青 (CEA) 对于无压轨道和冷回收至关重要.
- 乳化剂和青会影响水化和水泥微观结构,需要进行详细的研究.
- 了解这些相互作用是优化建筑应用中CEA性能的关键.
研究的目的:
- 研究不同脱硫率的阳离子乳化剂 (AEs) 和阳离子乳化青 (AEA) 对水泥水化的影响.
- 分析这些添加剂对水泥糊微观结构发展的影响.
- 为了阐明AEs和AEA在水泥水化中的抑制机制.
主要方法:
- 使用快速设置和缓慢设置的AEE及其相应的AEA准备改造的水泥糊.
- 测量设置时间,X射线衍射 (XRD) 和电电阻,以评估水分.
- 微结构分析使用入孔径测 (MIP) 和扫描电子显微镜 (SEM);化学分析使用能量分散谱仪 (EDS) 和里埃变换红外光谱仪 (FTIR).
主要成果:
- 证实AE和AEA都会延迟水泥水化,并改变水泥糊的微观结构.
- 缓定离子乳化青 (SAEA) 显示出最显著的影响,延迟了初始和最终的设置时间分别为73.9%和66.7%.
- SAEA增加了最可能的孔隙开口,并表明由于水泥颗粒上的碳基吸附而导致更强的抑制.
结论:
- 阳离子乳化剂和乳化青显著影响水泥水化动力学和微观结构.
- 缓缓设置的变种 (SAE和SAEA) 与快速设置的变种相比,对水泥水化有更强的减缓作用.
- 这些发现为AEA与水泥相互作用的机制提供了洞察力,这对于土木工程中的材料设计至关重要.
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