Influence of additives on the formation of electrodeposits in the concrete cracks

Abstract

The electrodeposition method for rehabilitation of the cracked reinforced concrete, based on the electrochemical technique, was presented here. The aim of this study was to evaluate the influence of additive on the formation of electrodeposits in the concrete cracks. Cracked mortar specimens of size 40 mm×40 mm×160 mm were immersed in electrolyte solutions(ZnSO₄, MgSO₄), and a constant current was applied between the reinforced steel and the external electrode for 15 days. Rate of surface coating, rate of crack closure and rate of crack filling depth were measured and the appearance of electrodeposits in the cracks was observed. The experimental results demonstrate that, under the experimental conditions, rate of surface coating and crack filling depth increase, while rate of crack closure decreases as the percengtage of additive increases. In addition, the electrodeposits become more denser and the microstructure varies with additive content, while the compositions of electrodeposits do not change.

Keywords

repair of cracks / additive / formation / microstructure

References

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