Corrosion inhibitors’ effect on design service life of RC structures

• Corrosion inhibitors’ performance is assessed through a probabilistic calculus of the design service life of RC structures.
• Two types of inhibitors are analyzed: added as an admixture to fresh concrete (AACI) and surface applied migrating (MCI).
• All cases show an increase in the design service life values with the influence of corrosion inhibitors.
• RC elements’ performance depends on: inhibitor type; surrounding environment; whether structures are new or existing.

The implementation of new data regarding the performance of corrosion inhibitors is applied through a performance-based method approved by recent European standards for the probabilistic calculus of service life of reinforced concrete structures. A set of concrete compositions was mixed in order to experimentally obtain strength – compressive – and durability properties – carbonation and chloride diffusion and together with the available results concerning the performance of two types of corrosion inhibitors three scenarios were defined for each concrete composition: (i) plain concrete; (ii) concrete with added admixture inhibitor and (iii) concrete with surface applied migration inhibitor. The probabilistic calculus of service life for each scenario was carried out using modeling equations in which the concrete properties were changed in view of the inhibitors’ performance characteristics. The results show that there is a significant improvement in the design service life when this is modeled considering the effect of corrosion inhibitors.