Corrosion of epoxy-coated rebar in marine bridges

Corrosion of epoxy-coated rebar in marine bridges - A 30 year perspective Conference

Sagüés, AA, Lau, K, Powers, RG et al. (2008). Corrosion of epoxy-coated rebar in marine bridges - A 30 year perspective . 5 2812-2828.

The corrosion performance of epoxy-coated rebar (ECR) over a nearly 30 year service period in Florida marine bridges is presented. Severe ECR corrosion was noted earlier in several of those bridges, built with relatively high permeability concrete. Corrosion development took place later in some other structures with less permeable concrete, with instances where the corrosion was associated with preexisting cracks. Corrosion was found to be associated with coating imperfections and coating disbondment. Laboratory experiments and modeling indicated that macrocell coupling with remote cathodes was an aggravating factor. Quantitative damage functions relating the observed deterioration with service time of the affected bridges are presented. A predictive corrosion initiation-propagation model was developed and the model output is compared with the field results to identify suitable parameters for forecasting future rehabilitation needs. The prognosis for future corrosion development is discussed, with attention to corrosion of ECR in otherwise low permeability concrete with preexisting cracks or local deficiencies. © 2009 by NACE International.