皮灰颗粒的作用和机制在水化过程中的水泥灰颗粒特征
Jialei Wang1,2, Xiaoqing Hu3, Feifei Jiang4
1School of Civil Engineering and Architecture, NingboTech University, Ningbo 315100, China.
Materials (Basel, Switzerland)
|November 27, 2024
概括
将反应性大米灰 (RHA) 添加到水泥糊中可以加速早期的水化,但可以延长诱导期. RHA增强了内部固化效应,促进了水泥的水化和pozzolanic反应,特别是在更高的含量.
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.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 反应性大米灰 (RHA) 是一个有前途的补充性水泥材料 (SCM).
- 了解RHA对水泥水化的影响对于开发先进的水泥复合材料至关重要.
- SCM的内部固化效应会影响水泥系统的长期性能.
研究的目的:
- 研究RHA含量对水泥水化动力学和产品的影响.
- 分析水泥-RHA糊中的内部固化机制及其周期性.
- 为了评估RHA对水泥水化和pozzolanic反应的影响.
主要方法:
- 准备了具有不同RHA含量的水泥复合糊.
- 用水合微热量计来测量热量流.
- 热重力测量和XRD (Rietveld) 分析量化了水化产品.
主要成果:
- 增加的RHA含量更早地转移了外热峰值,并增加了它们的幅度.
- 诱导期被延长 (例如,15%的RHA延长到3小时),而加速期则缩短.
- RHA表现出周期性的内部固化效应,在24小时后更早释放水分,并且在较高的RHA含量下加剧的显著后期效应 (7-28天).
结论:
- RHA既作为核化剂,又在早期水化过程中影响化学效应.
- RHA的内部固化作用是周期性的,并且取决于含量,增强了水泥的水化和RHA的pozzolanic反应.
- 较高的RHA含量显著促进了内部固化和pozzolanic活动,改善了水泥系统的性能.
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