贝灰基水泥材料的早期水化动力学:一个低场核磁共振研究
Chuan Tong1,2, Liyuan Wang1,3, Kun Wang1
1School of Civil Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel, Switzerland)
|July 30, 2025
概括
将贝灰 (SA) 添加到水泥糊中会改变水分和孔隙结构,最佳强度为5%SA. 更高的SA含量可能会阻碍水合,增加孔隙性,影响材料性能.
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.
- 物理化学 物理化学
背景情况:
- 可持续建筑材料对于减少环境影响至关重要.
- 贝灰 (SA) 是一种潜在的补充性水泥材料.
- 了解SA对水泥水化的影响对于其应用至关重要.
研究的目的:
- 调查不同灰 (SA) 含量对水泥早期水分演变,孔隙结构和水化动力学的影响.
- 为了确定最佳的SA含量,以提高机械性能.
- 为设计低碳水泥材料提供理论见解.
主要方法:
- 低场核磁共振 (LF-NMR) 用于水分演变和孔隙结构分析.
- 为了研究反应阶段,NG-I-D水化运动模型 (Krstulovic-Dabic).
- 机械性能测试 (压力强度).
主要成果:
- 酸盐含量显著影响水分分布和毛孔大小的发展.
- 孔隙性最初下降,然后随着SA含量增加,确定了最佳范围.
- 化动力学显示了三个阶段 (NG,I,D),其中扩散控制占主导地位.
- 在5%的SA含量下,峰值压力强度增加了18.6%.
- SA延迟核和晶体生长,影响微观结构.
结论:
- 特定的SA含量值控制了水合动力学和微观结构演变.
- 最佳的SA含量 (约5%),可以提高机械性能.
- 过度的SA (10%) 可能导致扩散受阻和异常多孔性.
- 这项研究为在可持续的水泥材料中利用SA提供了基础.
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