Efficiency of coatings applied on rebars in concrete
Source abstract
Abstract
The performance of three reinforcing steel bars (rebars) coatings is analyzed by means of electrochemical methods. The coatings are representative of those commonly used during the repair of concrete structures affected by corrosion in the coastal regions of Argentina: an epoxy rust conversion coating, a zinc-rich epoxy, and a sprayed zinc coating. Two exposure conditions were investigated: immersed in a saline solution (wet) and exposed to an indoors atmosphere (dry). The rebar corrosion potential (Ecorr), the corrosion rate (CR) and the electrical resistance (R) between bars were measured during approximately 800 days. In the dry condition the three coatings presented a satisfactory performance characterized by passive Ecorr values and CR values lower than 1 μm/year. On the other hand, the performance of the coatings in the wet condition depended on their formulations. The rust conversion coating showed active Ecorr values and CR values higher than those measured on the uncoated bars. The zinc-rich epoxy and the sprayed zinc coatings presented Ecorr values typical of active zinc. This indicates a certain degree of cathodic protection provided to the reinforcing steel. Besides, R values showed that in this condition, coatings do not provide a barrier type of protection.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Concrete Corrosion and Durability · Corrosion Behavior and Inhibition · Hydrogen embrittlement and corrosion behaviors in metals
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (21)
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