Non-destructive corrosion monitoring of steel reinforcement in concrete.

摘要

The inadequate and inaccurate application of corrosion monitoring techniques for testing reinforced concrete structures had led to considerable early deterioration of these facilities and has resulted in high restoration and replacement costs. The prospect and diligent use of readily available early damage detection tools for use in regular maintenance of these structures could permit timely interventions for restoration and upkeep.; This research program was aimed at determining the effectiveness of selected nondestructive testing methods as reliable indicators of early onset corrosion in steel-reinforced concrete. The methodology analyzed the onset of corrosion in a set of steel reinforcing rebars at a specific depth from the concrete surface, and used the resulting data as a predictor of corrosion activity in other reinforcing bars at different depths.; Two series of tests were conducted: the first series included nine individually reinforced concrete samples with varying cover thicknesses; the second series consisted of nine reinforcing steel bars, distributed equally in concrete specimens at different depths from the concrete cover. All specimens were subjected to accelerated corrosion using methods developed at McGill University to reproduce corrosion of steel rebars in a naturally aggressive environment as closely as possible.; The research results concur with the findings of other research programs, affirming that these monitoring tools are adequate predictors of corrosion. Nonetheless, they lack precision and are unable to track the time to corrosion initiation in structural concrete elements.