Electrochemical study on carbonated concrete after realkalisation

Abstract:

Electrochemical properties of carbonated concrete after realkalization were studied with electrochemical impedance spectroscopy (EIS) and polarization curves. The parameters of realkalisation are current density, 3A/m2 and 5A/m2, realkalisation time, 14days and 28days, the concentration of sodium carbonate solution, 1mol/L. The group of carbonated samples is 8. The first group is realkalisated, other seven groups were realkalisated every 1、2、3、8、9、10、13month. All samples are in the indoors. The electrochemical impedance spectroscopy (EIS), open circuit potential (OCP) and corrosion current were measured after the realkalisation experiment. The test result shows that the hydrogen generating at the cathode rebar during the experiment delay the re-passivation of rebar; Under the experiment conditions, the electrochemical properties of carbonated concrete after realkalization decay; From 10 months and 13 months after the realklaisation, the electrochemical properties are steady.

Key words:realkalisation; electrochemical impedance spectroscopy; polarization curve; reinforced