在水泥糊中孔结构的分析与微缩的天然热带石
Ionut-Ovidiu Toma1, George Stoian2, Mihai-Marius Rusu3
1Faculty of Civil Engineering and Building Services, The "Gheorghe Asachi" Technical University of Iasi, 700050 Iasi, Romania.
Materials (Basel, Switzerland)
|July 14, 2023
概括
将普通波特兰水泥替换为微化天然热带石,可以在水泥糊的早期阶段提升孔隙结构. 在28天后,10%的热带石与参考相匹配,而30%增加了孔隙大小,影响了混凝土的性能.
科学领域:
- 材料科学与工程 材料科学与工程
- 土木工程 土木工程是指土木工程.
- 地质化学 地质化学
背景情况:
- 不断增长的城市发展增加了对混凝土等建筑材料的需求.
- 减少混凝土对环境的影响至关重要,补充性水泥材料 (SCM) 提供了一个可行的解决方案.
- 由于其多孔结构,天然热石显示出增强基于水泥的材料的潜力.
研究的目的:
- 为了分析不同百分比的微化天然热石的水泥糊中的孔隙结构演变.
- 调查热替代物对水泥材料微观结构和性质的影响.
主要方法:
- 普通的波特兰水泥 (OPC) 取代了微化天然热带石,质量分别为10%,20%和30%.
- 核磁共振 (NMR) 放松计被用来研究孔隙结构在固化1,7和28天后的演变.
- 扫描电子显微镜 (SEM) 评估了在多个固化年龄 (1-28天) 的水泥糊的微观结构.
主要成果:
- 固化后的前7天内,含有热质的水泥糊呈现出较小的孔径.
- 在28天后,10%的热带石混合物显示出与参考混合物相比较的孔隙结构,这是由于增加了水化产品.
- 较高的替代水平 (30%的热) 导致较大的毛孔尺寸,这表明放松时间增加.
结论:
- 微型化天然热带石影响水泥糊的早期孔隙结构,通常是对其进行精炼.
- 在较晚的年龄段,孔隙结构精炼的最佳替换百分比似乎在10%左右.
- 更高的热酸盐含量可能会导致更大的孔隙,需要仔细考虑结构应用.
相关概念视频
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01:18Porosity in Cement Paste
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01:21Pozzolans
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01:12Total Voids in Concrete
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01:28Transition Zone
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