预先调节温度对活性混凝土的气体透性的影响
Patrycja Duży1,2, Marta Choinska Colombel2, Izabela Hager1
1Chair of Building Materials Engineering, Faculty of Civil Engineering, Cracow University of Technology, 31-155 Cracow, Poland.
Materials (Basel, Switzerland)
|June 10, 2023
概括
活性材料 (AAM) 在经受不同干燥温度时,气体透性和多孔性发生显著变化. 热预先调节对这些环保混凝土替代品的孔隙结构产生了重大影响.
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.
- 可持续建筑 可持续建筑
背景情况:
- 活性材料 (AAM) 为波特兰水泥提供了一个可持续的替代品,利用工业废物,如飞灰 (FA) 和磨砂颗粒高炉渣 (GGBFS).
- 活性混凝土 (AAC) 的广泛采用受到有限的标准化所阻碍,特别是在不同条件下的材料表征方面.
- 混凝土的标准测试协议通常涉及特定的干燥温度,这可能会不成比例地影响AAM特性.
研究的目的:
- 研究不同热预调温度对活性混凝土 (AAC) 的气体透性和孔隙结构的影响.
- 为了评估AAC变体 (AAC5,AAC20,AAC35) 具有不同的比例的GGBFS (5%,20%,35%) 在他们的活性结合剂.
- 要突出AAM气体透性对热预调的敏感性,这是其实际应用的关键因素.
主要方法:
- 具有不同GGBFS含量的AAC样品在20°,40°,80°和105°C的温度下进行预条件,直到恒定质量.
- 测量了所有预条件样本的气体透度.
- 通过入孔径测量 (MIP) 对在20°C和105°C预先调节的样本进行了孔径和孔径尺寸分布分析.
主要成果:
- 当在105°C预先调节时,低污泥AAC的整体孔隙性增加了高达3个百分点,而20°C时相比.
- 气体透率显著增加,高达30倍,取决于矩阵组成,在高温预先调节后.
- 热预先调节大大改变了孔径分布,对材料的整体性质产生了显著影响.
结论:
- 活性材料的气体透性和孔隙结构对热预先调节温度非常敏感.
- 传统混凝土使用的标准干燥温度可能不适合准确地描述AAM,可能导致误导性结果.
- 需要进一步的研究,以建立适当的AAM特性协议,以促进它们在建筑中的更广泛使用.
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