氯离子侵蚀引起的钢筋锈蚀是沿海或者盐湖地区混凝土结构耐久性劣化的主要诱因,现有氯离子侵蚀模型中的扩散系数多基于Fick's第二定律,由实验室试验或工程测试确定,具有一定的局限性.基于氯离子扩散系数试验数据,采用贝叶斯理论,建立了氯离子扩散系数计算模型.该模型综合考虑了水胶比、侵蚀时间、环境温度、相对湿度等因素对氯离子扩散系数的影响,能较好地反映氯离子扩散系数的变化情况.通过已有试验数据验证表明,该模型的计算结果与试验结果吻合较好,具有一定的理论和应用价值.
Reinforcement corrosion caused by chloride ion erosion is the main factor of durability deterioration of concrete structures in coastal or salt lake areas. The diffusion coefficient calculated by existing chloride ion erosion models is mostly based on Fick's second law, which is determined by laboratory test or field test. The calculation method has some limitations. Based on the experimental data of chloride diffusion coefficient and Bayesian theory, a calculation model of chloride diffusion coefficient was established. The model takes into account the effects of water-binder ratio, service time, ambient temperature and relative humidity on chloride diffusion coefficient, which can better reflect the variation of chloride diffusion coefficient. The validation of the existing experimental data shows that the calculated results of the model are in good agreement with the experimental results, and the established model has certain theoretical and practical value.
