再碱化后碳化混凝土电化学研究

Electrochemical Study on Carbonated Reinforced Concrete after Electrochemical Realkalisation Treatment

以电化学交流阻抗谱和再碱化模拟试验研究了再碱化对碳化混凝土中具有氧化层钢筋的作用;采用扫描电镜(SEM)结合能谱分析(EDS)对再碱化后具有氧化层钢筋的表面进行了分析.结果表明:再碱化过程中,钢筋电极表面的电化学反应与钢筋表面的状态密切相关;当钢筋电极表面存在氧化物时,再碱化使该氧化物的价态逐渐降低,并在钢筋电极表面形成单质铁,导致钢筋表面不易形成致密钝化膜.

The corrosion inhibiting behavior of rust rebar in carbonated concrete after electrochemical realkalisation treatment（ERT） was studied by electrochemical impedance spectroscopy（EIS） method and the realkalisation simulated test.The surface of rust rebar after ERT was analyzed by scanning electron microscope （SEM） coupled with energy dispersive spectroscopy（EDS）.The electrochemical reactions on the rebar in the carbonated concrete during realkalisation treatment were investigated by using simulated test and electrochemical measurement.The results show that the electrochemical reaction on the rebar is closely related to the situation on rebar surface.The Fe-oxides on rebar surface are partly changed to iron during ERT and the surface structure of rebar is complex;the passive film formed is not compact after ERT.