摘要
通过综合盐雾箱模拟滨海地区大气环境,采用安全壳同等级同配合比混凝土试件,经不同侵蚀时间,研究了盐雾环境下氯离子在安全壳混凝土中的扩散规律,并对Fick's第二扩散定律进行了修正。用修正模型进行数值分析,结果显示要让安全壳安全运行40年,则钢筋保护层厚度至少为51 mm;而想延寿至60年,则钢筋保护层厚度需要增加到56 mm。
Concrete specimens,with the same ratio of the containment concrete,were tested in salt spray test chamber which simulated the atmospheric environment in coastal area.The rule of diffusion of chloride ion into containment concrete had been discussed under different erosion time and improved Fick's second law.Using improved model for numerical analysis,the results showthat the thickness of cover should be at least 51 mm for the 40 years safe operation of the containment; if prolong life to 60 years,the thickness need to increase to 56 mm.
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