Long-term durability of electrochemical chloride extraction

This paper presents field data from one of the first well-documented reinforced concrete structures that has been rehabilitated with electrochemical chloride extraction (ECE) in the year 1989. The results of half-cell potential mapping measured 1, 5 and nearly 20 years after the ECE treatment show that the reinforcement was completely repassivated after the ECE treatment and remained in fully passive condition. Regarding the efficiency of the ECE treatment an intermittent (current on - off) is beneficial. The question of repassivation of pre-corroded reinforcement is discussed. According to this and other results from field applications the ECE treatment is effective and - if further chloride ingress is avoided - also durable. For economical reasons it is recommended to apply the non-destructive ECE treatment in an early state, before delaminations or spalling has occurred.