聚烯纤维对混凝土在冷解条件下和机械负荷下透性的影响
Wei Zeng1,2, Weiqi Wang1,2, Qiannan Wang1,2
1School of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310023, China.
Materials (Basel, Switzerland)
|June 27, 2024
概括
混凝土中的聚烯纤维 (PF) 降低了透气性,特别是在冷解周期和裂后. 它的效果在压力和拉力压力下变化,影响耐用性和防水应用.
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.
- 混凝土的耐用性 混凝土的耐用性
背景情况:
- 聚烯纤维增强材料 (PFRC) 越来越多地用于提高混凝土的耐用性.
- 了解聚烯纤维 (PF) 对混凝土透性的机制至关重要,因为人们对PFRC越来越感兴趣.
- 在冷解周期和应力下,PF对混凝土透性的影响是研究的一个关键领域.
研究的目的:
- 为了评估聚烯纤维 (PF) 对混凝土透性的影响.
- 研究PFRC透性在压力和拉伸应力下的行为,包括结解周期.
- 分析压力,体积变化和PFRC中的透性之间的关系.
主要方法:
- 在压力和拉力负荷下使用专用设置精确测量PFRC透性.
- 在压力负载下监测PFRC的体积变化.
- 应变-透度曲线的分析以及在最小透度和最小体积时的应力水平之间的相关性.
主要成果:
- PF对未损坏的混凝土的透性产生不利影响,但在破裂或融损坏的混凝土中降低了透性.
- 在压缩下,PFRC的透率最初下降,然后随着应力而增加,与体积变化相关.
- 在张力下,透性随着辐射变形和应变而增加;冷解周期在压缩下增加透性,但在张力下降.
结论:
- 聚烯纤维显著改变混凝土的透性,在受损或受天气影响的情况下提供好处.
- 应力状态 (压缩与拉力) 和环境因素 (结-解) 极大地影响PF对透性的影响.
- PF显示了增强混凝土防水性能的前景,并有可能被整合到结构设计的构成模型中.
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