和自然碳化演变对混合水泥糊的气体透性和微观结构的影响
Tomasz Tracz1,2, Tomasz Zdeb1,2, Krzysztof Witkowski3
1Faculty of Civil Engineering, Cracow University of Technology, Warszawska Str. 24, 31-155 Kraków, Poland.
Materials (Basel, Switzerland)
|September 27, 2025
概括
先进的气体透性测试显示,带有飞灰和渣渣添加剂的水泥复合材料在两年内由于持续的水化和碳化而减少了气体流量. 这项研究量化了水-水泥比率和添加剂对长期耐用性的影响.
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.
- 地质化学 地质化学
背景情况:
- 高性能水泥复合材料需要先进的方法来评估运输特性,特别是气体透性.
- 了解孔隙性和透性对于预测混凝土结构的长期耐用性和使用寿命至关重要.
研究的目的:
- 用修改气体透性方法评估混合水泥糊的质量运输能力.
- 调查水-水泥比率,添加剂 (飞,渣) 和自然固化 (90天至2年) 对糊的孔隙性和气体透性的影响.
- 分析由于水化和碳化而产生的微观结构变化及其对运输特性的影响.
主要方法:
- 使用修改后的RILEM-Cembureau方法进行气体透度测量,该方法适用于均糊.
- 通过核测量,侵入孔径测量和水和度的开放孔径评估.
- 微结构分析侧重于90天和2年的自然固化过程中的水化和碳化进展.
主要成果:
- 经过两年的自然固化,气体透系数 (k) 降低了11%至74%,根据水泥类型和水与水泥 (w/c) 的比率而有所不同.
- 持续的水合和碳化显著降低了透性,这表明材料随着时间的推移增强了密封性.
- 在w/c比率,添加剂,固化时间,多孔度和气体流量之间建立了定量相关性.
结论:
- 开发的气体透性方法是准确的,可靠的,对水泥材料的微观结构变化敏感.
- 长期的自然固化,包括水化和碳化,大大提高了混合水泥糊的耐用性,并降低了气体透性.
- 这些发现为工程应用提供了宝贵的见解,涉及水泥复合材料的长期性能和密封能力.
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