饱和状态下开裂混凝土内的氯离子输运

为得出饱和状态下氯离子在开裂混凝土内的输运规律，将饱和状态分为溶液静止和溶液流动2种情况；同时分别考虑表面氯离子质量分数与氯离子扩散系数的时变性和氯离子在混凝土内的线性结合理论，对前者采用传统的双重孔隙介质模型，对后者则采用二维扩散模型进行分析.基于Fick第二定律得出氯离子在裂缝和开裂附近混凝土内输运的计算方程，并根据裂缝自愈的影响对2种模型进行了修正.分别采用这2种模型对所设计的氯离子在预开裂混凝土试件内的侵蚀进行了计算.对比裂缝附近不同时间混凝土内氯离子质量分数的试验结果表明：短期侵蚀采用2种模型计算的结果均接近于试验值，长期侵蚀采用二维扩散模型能得到更加精确的结果.该结果为氯盐侵蚀下的混凝土结构耐久性设计与评估提供了参考.

Chloride ingression in cracked concrete under saturated state

Chloride transportation was divided into stationary and flowing solution states to investigate the mechanics of chloride transportation in cracked concrete under saturated condition. The behaviors of time-dependent surface chloride concentration and chloride diffusion coefficient in concrete were analyzed by dual porous medium model, and the behavior of linear bonding between concrete and chloride was analyzed by two-dimensional diffusion model, respectively. The governing equations of chloride ions diffusing into concrete and cracked concrete were described by the Fick’s 2nd law considering the effect of crack self-healing. Comparisons between the experimental and the numerical results showed the effectiveness of the proposed models. Dual porous medium model and two-dimensional diffusion model are both applicable for the short term ingression of chloride, and the two dimensional diffusion model is more appropriate to the long term simulation.