FraMCoS 8 2013 Toledo, Spain

Toward Hybrid-NDE for Rebar Corrosion in Reinforced Concrete with Acoustic Emission

For non-destructive evaluation (NDE) of corrosion in reinforcing steel-bars (rebar), a half-cell potential and a polarization resistance of the electrochemical methods are currently available. Since these techniques, however, evaluate surface values of concrete over rebars, it has been reported that…

First page of: Toward Hybrid-NDE for Rebar Corrosion in Reinforced Concrete with Acoustic Emission
Year 2013
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Abstract

For non-destructive evaluation (NDE) of corrosion in reinforcing steel-bars (rebar), a half-cell potential and a polarization resistance of the electrochemical methods are currently available. Since these techniques, however, evaluate surface values of concrete over rebars, it has been reported that the measured values are considerably affected by conditions of concrete cover. In this study, therefore, a procedure to estimate the potential distributions on rebars is developed by applying the boundary element method (BEM). An accelerated-corrosion experiment is conducted in a concrete–slab specimen. In order to monitor the corrosion process, acoustic emission (AE) measurement is performed during the test. Based on half-cell potentials and polarization resistances measured on the surface of the slab, potential distributions on rebars are estimated at the stages of high AE activities. Results are compared with direct observation of rebars, which are removed from the specimen. Thus, a great promise for a hybrid-NDE technique to quantitatively evaluate the corrosion process in reinforced concrete at an early stage is demonstrated.