化过程参数对RHA反应性和砂机械性能的影响
Jianrui Ji1,2, Lihui Li2, Lei Quan2
1School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China.
Materials (Basel, Switzerland)
|July 12, 2025
概括
优化大米灰 (RHA) 化改善了其色活性. 温度在600-700°C之间产生最佳的RHA,具有增强的反应性和混凝土强度.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 建筑材料 建筑材料
背景情况:
- 化参数的优化不足限制了大米灰 (RHA) 的pozzolanic活动.
- 米灰是一种从农业废物中提取的有前途的pozzolanic材料.
研究的目的:
- 为了研究烧温度,冷却模式,加热速率和保持时间对RHA波佐兰活性的影响.
- 优化RHA特性,以提高水泥材料的性能.
主要方法:
- 使用智能炉来对RHA化进行多参数合调节.
- 采用微观表征技术 (如XRD,SEM) 来分析RHA结构和组成.
- 评估了包含RHA.的水泥样本的pozzolanic活性和压力强度.
主要成果:
- 烧温度是影响RHA波佐兰活性的主导因素.
- 在600-700°C烧焦的RHA呈现出蜂多孔结构,高无形SiO2含量 (高达95%) 和优异的pozzolanic活性.
- 在800°C的化增加了RHA的结晶性,降低了它的活性.
- 用蒸水进行次冷处理,通过重建其状结构并降低结晶性,改善了RHA的反应性.
- 在600°C时化RHA的混凝土的3天压力强度高于在800°C时化RHA的混凝土.
结论:
- 对于RHA波佐兰活性来说,最佳的烧结温度在600-700°C之间.
- 控制的烧焦和后处理 (再冷却) 可以显著提高RHA的反应性.
- 优化的RHA可以提高混凝土的早期压力强度,提供可持续的建筑材料.
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