In the present paper, a simple model to predict the corrosion rate of steel bars in concrete is developed, considering the influence of the porosity of steel-concrete interfacial zone. Firstly, a model for the porosity of the interfacial zone is developed basing on the water-cement ratio gradient in the interfacial zone. Then the relationship between the porosity of the interfacial zone and the corrosion parameters of the steel bar in concrete is discussed, the anode-cathode ratio for the electrochemical corrosion process, the chloride threshold value and the resistivity of concrete are determined by the porosity of steel-concrete interfacial zone. The corrosion rate of steel bars, which is taken as the corrosion current density, is calculated by considering the cathodic concentration polarization of oxygen diffusion and resistance polarization of concrete, basing on the determined parameters above. Finally, the applicability and efficiency of the corrosion rate prediction model is verified by experiments.

在本文中，考虑到钢筋混凝土界面区域的孔隙率的影响，建立了一个简单的模型来预测钢筋在混凝土中的腐蚀速率。首先，基于界面区域水灰比梯度，建立界面区域孔隙度模型。然后讨论了界面区域的孔隙度与钢筋在混凝土中的腐蚀参数之间的关系，电化学腐蚀过程的阳极-阴极比率，氯化物阈值和混凝土的电阻率由钢筋的孔隙度确定混凝土界面区域。钢筋的腐蚀速率，即腐蚀电流密度，根据上面确定的参数，通过考虑氧扩散的阴极浓度极化和混凝土的电阻极化来计算Δε。最后，通过实验验证了腐蚀速率预测模型的适用性和有效性。