文章总结了国内外有关混凝土中氯离子侵蚀模型的研究现状,并对国内外几种典型的扩散方程进行了分析评价:针对氯盐侵蚀的预应力混凝土结构,讨论了氯离子扩散系数的计算。氯离子扩散系数对于预应力混凝土来说是一个重要的因素,因此合理确定氯离子扩散系数,对预测氯离子环境条件下预应力结构的耐久性具有重要意义。对于预应力混凝土,计算氯离子扩散系数除了要考虑混凝土与氯离子之间的结合能力、环境温度、湿度影响外,还要考虑混凝土的应力水平,氯离子有效扩散系数是变化的,且氯离子扩散系数对PC结构耐久性的影响很大。本文对预应力混凝土氯离子侵蚀模型进行了改进,并根据试验结果对改进后模型进行了评价。
Progress and achievement of modeling of chloride ingress in home and aboard are summarized and several typical diffusion equations are analyzed. The calculation of chloride diffusion coefficient in prestressed concrete structures eroded by chloride ion is discussed. Chloride diffusion coefficient, as a main factor, is significant to the durability of prestressed concrete in chloride ingress. Analytical results show that, except for the binding capacity between concrete and chloride ion, temperature and moisture, it is important to consider the stress of prestressed concrete. Chloride diffusion coefficient is variable and has large influence on durability of PC structure. Chloride ion erosion model for prestressed concrete is improved in the article. According to the experiment data, the improved model is evaluated.