揭示了长期暴露在水中的混凝土无性和孔隙结构的降解机制
Hua Wei1, Yi Sun2,3, Chunhe Li4
1Materials & Structural Engineering Department, Nanjing Hydraulic Research Institutes, Nanjing 210029, China.
Materials (Basel, Switzerland)
|February 13, 2026
概括
沿海水中的长期浸水混凝土显示出由于孔隙性增加而降低了不性. 盐水结晶和碳化是影响混凝土孔隙结构和性能随时间推移的关键因素.
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.
- 环境科学 环境科学
背景情况:
- 调查混凝土结构的长期耐用性对于基础设施安全至关重要.
- 了解在服务条件下混凝土孔状结构的演变,可以为维护和设计提供信息.
- 沿海环境中的水下混凝土面临着独特的退化挑战.
研究的目的:
- 分析浸水水混凝土中无性和孔隙结构的长期演变.
- 为了比较超过75年服务的水不同部分的混凝土的性能.
- 确定导致沿海环境中混凝土退化的因素.
主要方法:
- 系统地测试各种水部分的水下混凝土.
- 测量地表水的透阻力指数.
- 侵入孔径测量用于分析孔隙结构 (中位孔径,平均孔径,孔隙含量,孔隙性).
- 用X射线衍射 (XRD) 和扫描电子显微镜与能量分散光谱 (SEM/EDS) 进行材料分析.
主要成果:
- 与其他部分相比,主下游部分的混凝土具有明显较低的不透性 (9.19 × 10-9).
- 在降解部分的0-100毫米深度范围内,透性得到改善.
- 这部分的孔径中位数 (306.7 nm),平均孔径 (55.4 nm),孔径含量 (35.64%) 和孔径 (3.961 mm) 显著增加.
结论:
- 在沿海环境中长期暴露于盐溶液和碳化会降解混凝土.
- 结晶压力和碳化导致结构松动和多孔性增加.
- 这些微观结构的变化最终降低了水下大混凝土的透性能.
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