混凝土的风湿性行为,定时间,压力强度和微观结构,其中包含了补充的水泥材料和纳米
Chang Cai1, Qian Su1,2, Shaoning Huang1
1Institute of Civil Engineering Materials, School of Civil Engineering, Southwest Jiaotong University Chengdu Sichuan Province 610031 China chenzhao@swjtu.edu.cn.
RSC advances
|June 12, 2023
概括
这项研究研究了补充性水泥材料 (SCM),如二氧化烟雾 (SF),飞灰热层 (FAC) 和用于喷混凝土的砂中的纳米二氧化. 结果显示,SF,FAC和纳米二氧化的冲击形学和微观结构,增强压力强度和减少巨孔.
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.
- 建筑材料 建筑材料
背景情况:
- 优化砂性能对于喷混凝土应用至关重要.
- 补充性水泥材料 (SCM),如二氧化烟雾 (SF),飞灰热层 (FAC) 和纳米二氧化,为修改水泥粘合剂提供了潜力.
- 了解这些SCM对设置时间,风学和微观结构的影响对于性能预测至关重要.
研究的目的:
- 评估将普通波特兰水泥 (OPC) 替换为SF,FAC和纳米二氧化对砂定位时间和质性质的影响.
- 分析SCM修改砂的微观结构变化和压力强度的发展.
- 为了在射混凝土应用中提供最佳SCM含量的参考.
主要方法:
- 准备的砂糊和混合物含有不同级别的SF (5-7.5%),FAC (>20%),纳米 (1-3%) 的替代物.
- 测量了设置时间,粘度和产量压力.
- 微观结构使用侵入孔径学分析,并在不同的固化年龄确定压力.
主要成果:
- SCM显著影响了砂的风湿学;SF和纳米二氧化增加了粘度和产量应力,而FAC显示出更温和的影响.
- 压力强度的发展有所不同,SF5-FAC15组显示28天强度增长最高 (32.82%).
- SF5-FAC25-NS1.5混合物呈现出较小的宏孔面积和较细的孔径分布,表明微观结构紧性得到改善.
结论:
- 优化了SF,FAC和纳米的组合,可以满足喷混凝土的初始设置时间要求.
- 通过填充毛孔和精制毛孔大小分布,SCM增强了砂微结构,从而改善了机械性能.
- 该研究为高性能喷混凝土配方中有效利用SF,FAC和纳米提供了有价值的数据.
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