Electrochemical impedance spectroscopy characteristics of steel corrosion in seawater sea-sand concrete

Abstract

In this paper, the electrochemical mechanism and regularity of corrosion of steel bars in seawater sea-sand concrete under different chloride ion erosion styles are studied. Electrochemical impedance spectroscopy (EIS) was used to electrochemically test of steel bars in seawater sea-sand concrete (SSC). By means of analyzing the AC impedance spectra of the steel bars in specimens under two conditions, the conclusions can be gotten that in the EIS diagram of the steel bar in the rust state, the added capacitance arc in medium frequency range is related to pitting corrosion of the steel surface; The chloride ion carried by the aggregate and water decreased the concrete resistivity and transfer resistance of rebar and the anodic oxidation was easier to be carried out. In the equivalent circuit model, the constant phase element (CPE) is taken to replace the capacitor simulation in the equivalent circuit in order to simulate charge and discharge behavior of the electric double layer.