通过使用甲基来缓解活性渣的体积变化
Maïté Lacante1, Brice Delsaute1,2, Stéphanie Staquet1
1BATir Department (LGC), Université libre de Bruxelles (ULB), 1050 Brussels, Belgium.
Materials (Basel, Switzerland)
|June 13, 2025
概括
作为活性废渣水泥中的部分替代品,甲可林会影响基于激活剂类型和度的性能. 更高的替换增加了NaOH的强度,但减少了酸盐的强度,改变了体积稳定性和热膨胀.
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.
- 地质化学 地质化学
背景情况:
- 活性渣 (AAS) 水泥为普通波特兰水泥提供了可持续的替代品.
- 控制AAS的体积稳定性和机械性能对于实际应用至关重要.
- 在AAS中,甲可林作为补充的固材料被探索.
研究的目的:
- 在活性化系统中研究甲素作为渣渣的部分替代品的功效.
- 评估甲甲对AAS体积变化,压力强度和热性能的影响.
- 了解性激活剂类型 (NaOH与Na2SiO3) 和度对这些特性的影响.
主要方法:
- 用于制备带有活性废渣糊,具有不同的甲替代率 (0%,10%,20%,30%).
- 使用不同度的氧化 (NaOH) 和酸 (Na2SiO3) 的激活.
- 压力强度,可加工性,同热度计,自身应变和热膨胀系数 (CTE) 的评估.
主要成果:
- 使用8M和10MNaOH的甲醇替代剂增加了压缩强度,但使用Na2SiO3.3降低了压缩强度.
- 在10%的替代过程中,甲可林表现出稀释效应,在NaOH激活过程中出现了第三个反应峰值.
- 体积变化 (膨胀/收缩) 和CTE受到甲醇含量和激活剂类型的显著影响,更高的替代导致NaOH激活下增加收缩和CTE.
结论:
- 甲可可以减轻活性渣的体积变化,但它的效果高度依赖于激活器系统.
- 与甲甲替代的NaOH激活可以导致强度增加和热力学行为的改变,包括在更高的替代率下潜在的收缩问题.
- 激活Na2SiO3在减轻收缩方面显示出有前途,突出显示了需要仔细选择激活剂和混合设计的需要.
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