高性能混凝土的机械性能,腐蚀损害进化规律和耐久性恶化指标暴露于盐水土壤环境8年
Xiaoming Wang1, Hongfa Yu1,2, Yongshan Tan3
1School of Civil Engineering, Qinghai University, Xining 810016, China.
Materials (Basel, Switzerland)
|February 13, 2025
概括
这项研究调查了青海盐湖的高性能混凝土 (HPC) 腐蚀. 最佳的飞灰和二氧化烟雾含量,以及特定的水结合比率,提高HPC.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
背景情况:
- 目前关于混凝土腐蚀的研究经常使用模拟环境,缺乏现实世界的长期数据.
- 了解实际盐水条件下的混凝土降解对于基础设施的耐用性至关重要.
研究的目的:
- 评估高性能混凝土 (HPC) 在青海盐湖地区的自然条件下的长期耐腐蚀性.
- 为了确定不同的水结合比率 (W/B) 和飞灰 (FA) 含量对HPC耐用性的影响.
- 建立耐腐蚀性和关键材料特性之间的关系.
主要方法:
- 设计的HPC具有不同的混合比,适合青海盐湖环境.
- 暴露HPC样本在现场条件下长时间 (8年).
- 测量了超声速和压力强度,以评估腐蚀损伤的演变.
主要成果:
- HPC的耐腐蚀性受到W/B比率和矿物添加剂类型/剂量的显著影响.
- 在0.24-0.38.3的W/B比率下,在15-35%的飞灰和10%的二氧化烟雾下观察到最佳性能.
- 建立了耐腐蚀系数和相对动态弹性模量 (E) 和28天强度之间的相关性.
结论:
- 具有特定的飞灰和烟含量和W/B比率的HPC在高盐水中表现出优越的耐腐蚀性.
- 该研究为评估盐湖环境中的HPC腐蚀损伤提供了可靠的实验基础.
- 相对动态弹性模量 (E) 值为0.73-0.93,表明耐腐蚀性良好 (系数≥0.80).
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