二元和三元混合波特兰水泥,含有不同类型的米灰
Luis Miguel Ordoñez1, María Victoria Borrachero2, José Monzó2
1KhemeChemical S.L., Puerto de Sagunto, 46520 Valencia, Spain.
Materials (Basel, Switzerland)
|June 27, 2024
概括
米灰 (RHA) 可以取代波特兰水泥,但标准限制了其使用. 研究表明,反应性RHA最好用10%的替换,而反应性较低的RHA或飞灰允许混合水泥中的比例更高.
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:
- 米灰 (RHA) 是一种富含二氧化的农业废物,具有已被证明的pozzolanic特性.
- 目前的标准限制了RHA在混凝土和砂中的使用,特别是在像西班牙这样高产RHA的国家.
- 水泥行业面临着减少能源消耗和二氧化碳排放的压力,对矿物添加剂的兴趣日益增加.
研究的目的:
- 评估不同类型的RHA对混合波特兰水泥性能的影响.
- 确定水泥配方中RHA的最佳替代水平.
- 探索设计新混合水泥标准的潜力,包括RHA.
主要方法:
- 对各种RHA类型的波佐兰活性 (特定表面积,无形含量) 的表征.
- 使用RHA和飞灰对二元和三元混合水泥的实验性制备.
- 混合水泥的可加工性和28天机械性能的评估.
主要成果:
- 由于可加工性问题,高度反应的RHA (高表面积,无形) 仅限于10%的水泥替代.
- 较少反应的RHA或飞灰可以与混合水泥中的反应性RHA相结合.
- 可以设计出像CEM II/A-H,CEM II/A-H-V和CEM II/B-H-V这样的水泥.
结论:
- 使用高达30%RHA的混合水泥可以达到与传统波特兰水泥相比的28天机械性能.
- 该研究证明了将RHA纳入标准化水泥类型的技术可行性.
- 优化RHA反应和混合策略是最大限度地利用其在可持续建筑中的关键.
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