摘要
氯离子侵蚀引起钢筋锈蚀是沿海地区钢筋混凝土结构失效的一个主要原因.目前在应用Fick定律进行氯离子扩散分析时,一般不考虑混凝土对氯离子的固化作用以及扩散系数在服役期间的变化.本文基于Fick第一、第二扩散定律,提出了一种简单而可靠的推算氯离子质量分数的方法.该方法考虑了混凝土对氯离子的线性固化,以及扩散系数在服役期间的变化.根据一个自然环境中对混凝土试件现场氯离子质量分数试验的数值分析发现,混凝土中的氯离子质量分数随服役时间的增加而增加,随扩散深度的增加而减少.氯离子扩散系数是一个随时间、扩散深度和氯离子质量分数变化的变量.
Chloride-induced corrosion is a major cause of the deterioration for RC(reinforced concrete) structures exposed to marine environment. In practice,application of Fick's law to chloride diffusion in concrete is usually done without considering the chloride binding capacity of mortars and diffusivity as a variable. Based on Fick's first and second laws,a simple and reliable method to predict the distribution of chloride concentration was presented. Linear chloride binding and time-dependent diffusivity was taken into account in this approach. Based on a chloride concentration test of field-exposed concrete specimens,a numerical example was given. The result shows that the chloride concentration increases with service time,decreases with diffusion depth,and the chloride diffusivity is a variable with time,depth and chloride concentration.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2004年第2期195-199,共5页
Journal of Zhejiang University：Engineering Science
