Study of the effectiveness of realkalisation treatment on reinforcement repassivation by using simulated concrete pore solution

This work studies the effectiveness of realkalisation treatment on reinforcement repassivation by using simulated concrete pore solution. Two alkaline solutions were adopted and six different corrosion exposure times were analysed. Results show that higher alkaline media were more favourable to reinforcement repassivation after realkalisation and that there is a limit of 28 days of reinforcement exposure to corrosion from which the repassivation tends to be more difficult to be reached. This limit corresponds to average corrosion depths of 3.7 mu m for solution 1 and 0.7 mu m for solution 2. The effectiveness of realkalisation in recovering the initial levels of E-co(rr) and i(co)(rr) can be analysed by the parameters E-index and i(index). These parameters decrease with the exposure time to corrosion and with the average corrosion depth, being this decrease stronger for i(index). This general behaviour was also confirmed by EIS measurements. Considering the few studies on this topic, more research is necessary, including concrete structures, to enlarge the literature database and reach more widely based tendencies.

Automated summary

This study investigates the effectiveness of realkalisation treatment on reinforcement repassivation using simulated concrete pore solution. The results suggest that higher alkaline media are more beneficial for reinforcement repassivation after realkalisation. Furthermore, there is a limit of 28 days of reinforcement exposure to corrosion from which repassivation becomes more difficult to achieve. The effectiveness of realkalisation can be analysed using the parameters E-index and i-index, which decrease with exposure time and corrosion depth.