中文摘要：

为了抑制氯离子反向扩散造成钢筋二次腐蚀，进一步延长修复后混凝土结构的服役寿命，在电化学除氯（ECR）基础上提出一种通过电驱动SiO3^2-进入孔隙，与孔隙中的Ca（OH）2反应生成C-S-H凝胶硬化混凝土／砂浆，并同时去除混凝土／砂浆内氯离子的新型的联合修复方法。由对比试验，通过滴定氯离子，利用自腐蚀电位（Ecorr）、腐蚀电流密度（Icorr）和电化学阻抗谱法（EIS）研究了该方法的修复效果及其修复后的长期耐久性，此外，由压汞法和热重分析探讨了该方法的微观作用机制。结果表明：联合修复方法与电化学除氯具有相近的除氯效率；与电化学除氯相比，联合修复方法能更有效延缓钢筋的二次腐蚀；随着初始氯离子含量的减少，联合修复方法延缓钢筋二次腐蚀的效果更为显著；联合修复方法对钢筋二次腐蚀的抑制源于其致密化作用，经联合修复后砂浆总孔隙率与有害孔数量相比于修复前均有所下降。

英文摘要：

For the aim of suppressing the reverse diffusion of chlorine ions and further extending the service life of concrete structures after remediation, a novel remediation method of combining electrochemical chloride removal （ECR） with electro-migration of silicate ion has been developed. By a comparative experiment, the efficiency of chloride removal and corrosion properties of steel reinforcement in mortar specimens after remediation were investigated by means of chloride potentiometric titration, corrosion potential （Ecorr） and corrosion current density （Icorr） determined by electrochemical impendence spectroscopy （EIS）. Besides, the mortar microstructure was characterized by mercury intrusion porosimeter and thermogravimetric analysis. The results showed that the combined remediation had a similar efficiency of chloride removal when compared with the electrochemical chloride removal method. Moreover, the combined remediation method could effectively reduce the corrosion rate of steel reinforcement for the second time. With the decrease of initial chloride content, the efficiency of reducing the corrosion rate of steel reinforcement for the second time would be improved after the combined remediation. The corrosion of steel reinforcement for the second time could be inhibited effectively after the combined remediation method, owing to densification by electro-migration reaction of silicate ion. After the combined remediation, the porosity and the harmful pore number were reduced.