Assessing damage in corroded reinforced concrete using acoustic emission

The acoustic emission (AE) behavior of reinforced concrete beams tested under flexural loading was investigated to characterize and identify different sources of damage including microcrack development, localized crack propagation, and debonding of the reinforcing steel. By testing plain, notched-plain, reinforced, and corroded-reinforced specimens, different damage mechanisms were isolated and characterized. AE events were analyzed using conventional AE parameters. In addition, waveform analysis was conducted using both fast Fourier transform and wavelet transform methods. AE event rate and AE generation behavior showed different aspects depending on the degree of corrosion of reinforcing steel. The results of the cross-plot, typically amplitude versus duration, showed a clear difference with each stage of damage. Both AE parameter analysis and waveform analysis exhibited a favorable correlation with the condition of damage in the reinforced concrete beams. As a result, AE may provide a promising method to estimate the damage of reinforced concrete structures.