通过复合早期强度剂修改的双液体接材料的早期水化机制研究
Xinming Chen1,2, Jie Wang1,2, Huazhe Jiao1,2
1Henan Key Laboratory of Underground Engineering and Disaster Prevention and Control, Henan Polytechnic University, Jiaozuo 454150, China.
Materials (Basel, Switzerland)
|October 14, 2023
概括
这项研究通过使用复合早期强度剂来增强基于硫酸水泥的双液体接材料 (SACDL). 优化的混合物显著减少了定时间,并提高了早期的压力强度,提高了材料性能.
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:
- 基于硫酸水泥的双液体接材料 (SACDL) 需要可调节的设置时间和改善的早期强度,以实现实际应用.
- 现有的配方可能无法满足快速施工和高早期性能的苛刻要求.
研究的目的:
- 研究酸盐,硫酸,碳酸和复合早期强度剂对SACDL的设置,硬化和早期水化的影响.
- 为了优化早期强度剂的组成,以提高性能.
- 为了阐明SACDL在复合剂的影响下的早期水化机制.
主要方法:
- 在SACDL面料上进行了定时间,流动性,压力强度和粘度测试.
- 使用X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 来分析水化产品和微观结构的演变.
主要成果:
- 由0.8%的酸盐和0.5%的硫酸组成的复合物显著减少了初始设置时间至5分钟,最终设置时间至10分钟.
- 三小时压力强度达到16.7 MPa,比对照组增加31%.
- 复合剂加速了化 (AFt) 和酸水合物 (C-S-H) 凝的形成,导致更密集的微观结构.
结论:
- 酸盐和硫酸的协同作用有效地加速SACDL的水合,缩短定时间,并增强早期的强度.
- 该研究揭示了加快C3S和C2S溶解的机制,并促进了CH的结晶和C-S-H凝的形成.
- 优化的复合材料早期强度剂为开发高性能SACDL接材料提供了可行的解决方案.
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