环境固化高基活性化工程复合材料的收缩,透和冷解特性
Khandaker M A Hossain1, Dhruv Sood1
1Department of Civil Engineering, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada.
Materials (Basel, Switzerland)
|November 25, 2023
概括
这项研究引入了可持续的,无水泥的活性化工程复合材料 (AAEC) 与聚乙醇 (PVA) 纤维. 这些材料表现出有前途的机械强度和耐用性,与传统的工程混凝土复合材料 (ECC) 相美.
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.
- 可持续的建筑材料 可持续的建筑材料
背景情况:
- 传统的水泥生产对环境产生了重大影响.
- 开发可持续的替代品,如活性材料至关重要.
- 工程混凝土复合材料 (ECC) 提供增强的柔性,但通常依赖于水泥.
研究的目的:
- 开发和评估可持续的,无水泥,单部分,环境固化活性工程复合材料 (AAECs).
- 评估包含聚乙烯醇 (PVA) 纤维的AAEC的耐用性和微观结构特征.
- 为了比较AAEC与传统工程混凝土复合材料 (ECC) 和活性砂 (AAM) 的性能.
主要方法:
- 使用飞灰 (C类和F类),磨砂颗粒高炉渣 (GGBFS),砂和粉末形式的性试剂来制定AAEC.
- 评估了机械性能 (压力强度),尺寸稳定性 (膨胀/收缩,质量变化) 和耐用性 (吸附性,抗解).
- 通过结合相的形成 (C-A-S-H,C-S-H,N-C-A-S-H,N-A-S-H) 隐含考虑了微结构分析.
主要成果:
- 开发的AAEC实现了令人满意的压力强度在34MPa至46MPa之间.
- 二元前体组合 (FA-C + GGBFS) 与试剂2 (氧化 + 硫酸) 由于结晶相形成而表现出较低的收缩率.
- 在控制ECC时,AAEC显示出优越的透电阻 (较低的二次吸附性) 和可比的冷解电阻 (RDME > 90%在300个周期).
- 与AAM相比,AAEC中的纤维强化和矩阵密集化减少了收缩和质量变化.
结论:
- 使用粉末形式的试剂可以生产具有PVA纤维的可持续,无水泥的AAEC.
- 这些AAEC表现出令人满意的机械性能和增强的耐用性,包括良好的抗收缩,透和冷解周期.
- 这些发现证实了应变硬化AAEC的生产可行性,作为传统水泥基材料的可行可持续替代品.
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