Epoxy-coated reinforcement in concrete structures: Results of a Swiss pilot project after 24 years of field exposure

• Published in: Materials and corrosion 2016-06, Vol.67 (6), p.631-638
• Main Authors: Keßler, S., Angst, U., Zintel, M., Elsener, B., Gehlen, C.
• Format: Article
• Language: English
• Subjects: cathodic disbondment; Chlorides; coating defects; Concrete; concrete structure; Concretes; Corrosion; Defects; electrochemical measurement methods; epoxy-coated reinforcement (ECR); Exposure; Pilot projects; Reinforcement; Reinforcing steels; Strategy
• ISSN: 0947-5117; 1521-4176
• DOI: 10.1002/maco.201608863

Reinforced concrete is the most common construction material of civil infrastructure. In severe environment, e.g., chloride exposure, concrete deterioration can occur with consequences on the durability of the structure. The use of epoxy‐coated reinforcement is a strategy to control chloride‐induced reinforcement corrosion, particular by prolonging the initiation and propagation phase. The epoxy‐coating acts as a physical barrier to chlorides and the electrolyte concrete. However, the effectiveness of the strategy in chloride environment and the corrosion performance of ECR in presence of coating defects is investigated by condition assessment of a Swiss pilot project after 24 years of field exposure. This paper reports results on the performance of epoxy‐coated reinforcing (ECR) steel in concrete after 24 years of field exposure in Central Europe. The bridge inspection included common inspection methods. Furthermore, chloride profiles were taken and half‐cell potential mapping was executed. On the ECR segments with defined coating defects, a number of electrochemical and electrical measurements were performed on‐site and in the laboratory.