Efficiency investigations of electrochemical realkalisation treatment applied to carbonated reinforced concrete — Part 1: Sacrificial anode process

• Published in: Cement and concrete research 2012, Vol.42 (1), p.84-94
• Main Authors: Tong, YunYun, Bouteiller, Véronique, Marie-Victoire, Elisabeth, Joiret, Suzanne
• Format: Article
• Language: English
• Subjects: Applied sciences; Art and art history; Buildings. Public works; Carbonation; Carbonation (B); Cements; Chemical Sciences; Concrete (E); Concretes; Concretes. Mortars. Grouts; Corrosion; Corrosion potential; Current density; Electrochemical properties (C); Engineering Sciences; Exact sciences and technology; Humanities and Social Sciences; Materials; pH (A); Reinforced concrete; Reinforcement (D)
• ISSN: 0008-8846; 1873-3948
• DOI: 10.1016/j.cemconres.2011.08.008

The aim of this study was to assess the efficiency of a realkalisation treatment using sacrificial anodes applied to reinforced concrete degraded by carbonation. Analytical determinations (acid/base indicators, quantitative pH, alkaline profiles, SEM and micro-Raman) together with electrochemical characterizations (rest potential, impedance, linear polarisation resistance and corrosion current densities) were performed on artificially carbonated slabs, before and after treatment (mainly 15 days, 11 weeks, 6 and 12 months). The treatment efficiency was demonstrated by an increase of pH and by an alkaline ion penetration in the concrete cover. Rest potential and corrosion current densities indicated a slight decrease of the rebar corrosion activity. Complementary Raman spectroscopy showed a change in the oxide species and SEM observations indicated that the cement matrix remained almost unchanged.