关于激活砂飞灰水泥材料收缩的研究
Peng Cui1, Yuanyuan Wan2, Xuejun Shao3
1School of Transportation and Civil Engineering, Nantong University, Nantong 226019, China.
Materials (Basel, Switzerland)
|June 10, 2023
概括
活性废渣水泥为传统水泥提供了一个低碳的替代品. 添加飞灰和细砂有效减少收缩,尽管它可能会影响机械强度.
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:
- 传统的酸盐水泥生产产生大量的二氧化碳,需要环保的替代品.
- 活性废渣水泥 (AASC) 是一种具有低碳排放和废物利用率的可持续选择.
- 与传统混凝土相比,AASC具有优越的性能,但可能会受到较大的收缩.
研究的目的:
- 调查飞灰和细砂含量对AASC干燥和自生收缩的影响.
- 分析孔隙结构变化和AASC中的收缩行为之间的关系.
- 为了确定减轻AASC收缩的最佳添加剂水平.
主要方法:
- 使用了废渣粉和酸盐 (水玻璃) 作为原材料.
- 在AASC混合物中加入不同百分比的飞灰和细砂.
- 测量干燥收缩和自身收缩,与毛孔结构分析相关联.
主要成果:
- 添加飞灰和细砂有效地减少了AASC的干燥和自身缩.
- 增加的添加剂含量导致收缩减少,但也减少了机械强度.
- 在60%的飞灰下,干燥收缩率降低了30%左右,原生收缩率降低了24%.
- 在40%的细砂下,干燥收缩率降低了~14%,自生收缩率降低了~4%.
结论:
- 飞灰和细砂在减少AASC收缩方面是有效的,而飞灰显示出更大的影响.
- 在AASC配方中,减少收缩和机械强度之间存在一个权衡.
- 优化飞灰和细砂含量对于开发高性能,低收缩的AASC至关重要.
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