盐含量对C-S-H凝和Ca(OH)2在不同固化温度下的微结构发展的影响
Wenjie Qi1, Zhisheng Fang1, Shiyi Zhang1,2
1School of Civil Engineering and Geomatics, Shandong University of Technology, Zibo 255000, China.
Materials (Basel, Switzerland)
|September 28, 2024
概括
在混凝土混合物中使用海水可以增强水化产品的形成,特别是酸 (C-S-H) 凝和氧化 (CH),特别是在高温下. 飞灰的添加进一步增强了C-S-H凝,同时降低了CH含量,改善了混凝土的微观结构.
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.
- 混凝土技术 混凝土技术
背景情况:
- 沿海建筑面临淡水短缺,促使在混凝土混合物中使用海水.
- 海水中的离子可能会对水泥水化和混凝土的耐用性产生负面影响.
- 了解海水混合混凝土中的水化产品形成对于结构完整性至关重要.
研究的目的:
- 研究海水混合对水合酸盐 (C-S-H) 凝和氧化 (CH) 生产在水泥糊中的影响.
- 分析离子剂量,飞灰添加和固化温度对水化产品的影响.
- 通过使用灰色相关性分析来确定影响因素和水化产品形成之间的相关性.
主要方法:
- 不同扫描热量计 (DSC) 分析.
- 进行X射线衍射 (XRD) 分析.
- 扫描电子显微镜 (SEM) 用于微观形态学.
- 对因素影响的灰色相关性分析.
主要成果:
- 与标准固化相比,较高的固化温度 (50°C) 显著促进了水化反应,并增加了C-S-H凝和CH含量.
- 离子剂量与C-S-H凝和CH含量正相关;1.3%的剂量在50°C时增加了13.5%的C-S-H凝.
- 在50°C固化下,飞灰添加增加了C-S-H凝含量 (5.02%在25%飞灰下),同时降低了CH含量 (31.8%降低在25%飞灰下).
- 水解产物 (C-S-H凝和CH) 随着固化年龄的增加,导致更密集的微观结构.
- 飞灰剂量显示出与CSH凝和CH含量的灰色相关性最高.
结论:
- 海水可以有效地作为混凝土的混合介质,高温可以增强有益的水合产品.
- 飞是一种有价值的添加剂,可以改善C-S-H凝的形成,并减轻海水混合混凝土中的CH含量.
- 优化化物剂量,飞灰含量和固化条件是提高沿海环境中混凝土结构耐用性和性能的关键.
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