热周期对RPECC机械性能的影响:静态和动态压缩性能
Shaohua He1, Zhiliang Chen1, Changxi Liu1
1School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, China.
Materials (Basel, Switzerland)
|June 27, 2025
概括
这项关于-聚乙烯纤维增强工程水泥复合材料 (RPECC) 的研究发现,虽然增强了性,但最佳含量是20%的应变率灵敏度. 热循环显著降低了RPECC的性能.
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.
- 复合材料 复合材料 复合材料
背景情况:
- 工程混凝土复合材料 (ECC) 是具有增强柔性的先进材料.
- 将颗粒和聚乙烯纤维纳入ECC (RPECC) 旨在提高性和能量吸收.
- 在热循环等环境压力因素下了解RPECC的行为对于实际应用至关重要.
研究的目的:
- 研究不同颗粒含量和热循环对RPECC的静态和动态压缩性能的影响.
- 分析受热循环影响的RPECC中的微结构变化.
- 在RPECC中确定最佳的含量,以平衡强度,柔性和拉伸率灵敏度.
主要方法:
- 在RPECC上进行了静态和动态压缩测试,其含量不同 (10-30%).
- 标本受到270个周期的热负荷.
- 扫描电子显微镜 (SEM) 和能量分散式X射线光谱 (EDS) 用于微观结构分析.
主要成果:
- 将含量增加到30%提高了性,但将静态压力强度降低了高达17.9%.
- 热循环导致静态 (18.0%) 和动态 (41.2%) 压力强度的显著降低.
- RPECC表现出应变率的敏感性,20%的含量被认为是动态增强的最佳;更高的含量减少了这种效应.
- 热循环促进了水化产品的形成和界面缺陷,导致性能降低.
结论:
- 对RPECC的最佳含量约为20%,以最大限度地提高拉伸率的灵敏度和柔性.
- 热循环显著降低RPECC的机械性能,需要在设计时考虑.
- 微结构分析显示,水化产品的形成和界面缺陷是热应力下RPECC降解的关键因素.
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