Alternating current (AC) impedance spectroscopy has been applied in characterizing
microstructural evolution and electrochemical properties of cement-based systems. In the present
paper, an equivalent circuit model was proposed to study the influences of chloride binding on
microstructure and solid-liquid interfacial properties of cement paste. Chloride concentration index of
pore solution was measured to correlate to the parameters in equivalent circuit model corresponding
to electrical double layer at solid-liquid interface. The results showed that the parameters of
equivalent circuit model can properly indicate the microstructure and interfacial properties of cement
paste. Resistance of continuous pores was gradually decreased with chloride concentration in soaking
solution due to the higher conductivity of pore solution. The capacitance of electrical double layer was
increased with chloride concentration in pore solution due to more content of chloride ions in
electrical double layer. While the thickness of electrical double layer was decreased as chloride
concentration increased, which is in agreement with mathematical calculation.
Discussion(0)
No comments yet. Be the first to comment.