前体材料和激活剂相互作用对一个部分活性混凝土微观结构和机械性能的影响
Mohamed I Serag1, Sara Ibrahim1, Amr H Badawy2
1Faculty of Engineering, Cairo University, Giza, Egypt.
Scientific reports
|August 7, 2025
概括
一部分活性混凝土简化了准备,提高了可持续性和性能. 这项研究揭示了前体材料和激活剂如何影响微观结构和机械性能,从而导致优化,低CO2混凝土配方.
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) 为普通波特兰水泥 (OPC) 提供了可持续的替代品.
- 传统的两部分AAMs需要单独制备性溶液,这就带来了实际挑战.
- 一部分的AAM将激活剂整合到混合物中,简化生产并提高一致性.
研究的目的:
- 研究不同激活剂对一部分活性混凝土的机械性能和微观结构的影响.
- 了解前体材料和激活剂化学在AAM开发中的作用.
- 确定最佳配方,以提高性能和减少对环境的影响.
主要方法:
- 使用各种激活剂和前体材料 (污泥,石) 制备和表征单部分活性混凝土.
- 机械性能测试,重点是压力强度.
- 使用扫描电子显微镜 (SEM) 和能量分散式X射线光谱 (EDAX) 进行微结构分析,以确定元素组成和相位形成.
主要成果:
- 只有渣的AAM显示了--酸盐水合物 (C-A-S-H) 和--酸盐水合物 (N-A-S-H) 凝的密集微结构.
- 添加本托尼特导致异质的微结构具有更高的含量,表明复杂的N-A-S-H形成.
- 一种最佳的三元激活剂 (6:3:1酸:氧化:碳酸) 与OPC相比,产生了47MPa的压力强度和80%的CO2排放量减少.
结论:
- 选择前体材料和选择激活剂对于定制AAM属性至关重要.
- 一部分的AAM为可持续建筑提供了一条可行的途径,其性能与OPC相比或更高.
- 优化的配方,如三元激活器系统,可以显著提高机械强度,减少环境足迹.
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