化水泥糊的热活性化:对水泥化的性能和影响
Asghar Gholizadeh-Vayghan1, Guillermo Meza Hernandez2, Felicite Kingne Kingne2
1Vlaamse Instelling voor Technologisch Onderzoek, 2400 Mol, Belgium.
Materials (Basel, Switzerland)
|June 19, 2024
概括
热激活水泥糊 (DCPs) 显示在更高的温度下反应性增加. 然而,在混合水泥中,通过适度的热处理 (350°C) 实现了最佳的机械性能,平衡了反应性和水分.
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:
- 补充性水泥材料 (SCM) 对于可持续混凝土至关重要.
- 热激活是一种增强SCM的特性的一种方法.
- 了解热处理对水泥性能的影响至关重要.
研究的目的:
- 研究热激活水泥糊 (DCPs) 的性能和水泥性能.
- 评估在各种热条件下产生的DCPs作为混合水泥中的SCM的影响.
- 分析DCPs对新型水泥系统的机械性能和水化动力学的影响.
主要方法:
- 波特兰水泥和渣渣混合水泥糊在350°C,550°C和750°C的温度下经过热处理,持续时间不同.
- DCP属性的表征包括可研磨性,BET特定表面积和C2S相形成.
- 混合水泥的评估涉及机械性能测试和水化研究.
主要成果:
- 增加的热处理温度和持续时间提高了DCP研磨能力,表面积,C2S形成和SCM反应性.
- 在350°C处理2小时的DCP在混合水泥中产生了最佳的机械强度.
- 高度反应的DCP (来自更高的温度) 对波特兰水泥的早期水化产生了负面影响,导致设置问题和缓慢的强度增加.
- 在使用反应性DCP时,三级渣泥-DCP混合物显著增加了早期强度.
结论:
- 热处理显著改变DCP属性,影响它们作为SCM的性能.
- 对DCP的最佳热处理取决于应用,适度的温度有利于二元混合物的机械强度.
- 反应式DCP可以提高三元泥混合物的早期强度,但由于水化干扰,需要在二元波特兰水泥系统中仔细考虑.
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