This work studied the passivation of steel bar in cement pastes prepared with and without nano-silica by using electrochemical measurements and surface characterization methods. The results showed that the passivation of steel bar in cement paste was dominated by the chemistry of the pore solution and the evolution over time, which are closely associated with the hydration process of the cement. The addition of nano-silica influenced the alkalinity of the pore solution in cement paste and modified the pore structure of the cement paste, which resulted in a different passivation process and a thicker passive film with a higher proportion of Fe²⁺ oxides. The intrinsic corrosion resistance of steel bars in concrete prepared with nano-silica was expected to be enhanced.

这项工作通过电化学测量和表面表征方法研究了在有或没有纳米二氧化硅的水泥浆中钢筋的钝化。结果表明，水泥浆中钢筋的钝化主要受孔隙溶液化学性质和随时间演变的影响，这与水泥的水化过程密切相关。纳米二氧化硅的加入影响了水泥浆中孔隙溶液的碱度，改变了水泥浆的孔隙结构，从而导致钝化工艺不同，钝化膜更厚，Fe ²⁺氧化物的比例更高。预期使用纳米二氧化硅制备的混凝土中钢筋的固有耐腐蚀性会增强。