脱冰盐与含有砂水泥的混凝土糊的化学相互作用
Mohsen Torabi1, Peter C Taylor1,2
1Department of Civil, Construction & Environmental Engineering, Iowa State University, Ames, IA 50011, USA.
Materials (Basel, Switzerland)
|September 13, 2025
概括
脱冰盐会导致渣泥糊的化学质量明显恶化,主要是通过Friedel的方法.
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.
- 混凝土的耐用性 混凝土的耐用性
背景情况:
- 石灰泥混凝土易受脱冰盐的化学攻击.
- 了解盐引起的腐蚀机制对于混凝土的寿命至关重要.
研究的目的:
- 为了研究暴露在化物除冰盐中的渣泥糊的化学恶化.
- 阐明弗里德尔盐 (FS) 和氧化在混凝土降解中的作用.
- 为了确定盐类型,度和温度对这些反应的影响.
主要方法:
- 在不同度和温度下,将渣泥糊暴露在各种脱冰盐溶液 (CaCl,MgCl,NaCl) 中.
- 使用X射线衍射 (XRD) 分析反应产物和相变.
- 使用诱导合等离子体 - 光学发射光谱法 (ICP-OES) 量化溶解物种.
主要成果:
- 弗里德尔盐 (FS) 的形成和随后在CaCl2和MgCl2溶液中不相称的溶解会比氧化的形成造成更大的损害.
- 氧化可以在糊中持续存在,而FS溶解有助于材料损失.
- 渣泥中较高的AFm相含量加剧了FS相关的恶化.
- 与CaCl2和MgCl2相比,NaCl的恶化程度较小.
- 盐度影响相位稳定,导致相位的重新出现和消失.
结论:
- 在化物攻击下的渣水泥糊中化学恶化的主要机制涉及弗里德尔盐 (FS) 溶解.
- 特定阶段的漏洞,特别是FS和AFm阶段的漏洞,决定了损坏的程度.
- 了解这些机制可以更好地预测和减轻混凝土结构中脱冰盐损伤.
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