Deterioration of structural parameters due to corrosion in prestressed concrete identified by smart probe-based piezo sensor

In this paper, the deterioration of structural parameters namely equivalent stiffness, mass and damping due to corrosion in prestressed concrete (PC) structures using a smart probe-based piezo sensor (SPPS) via electro-mechanical impedance (EMI) technique is presented. The effectiveness of the SPPS was first demonstrated qualitatively by a change in the raw conductance signatures during the corrosion progression and different phases of corrosion (initiation, propagation, and cracking) was identified by the quantitative statistical damage indices. Assessment of material degradation under chloride-laden environment was done using equivalent structural parameters identified by SPPS from the raw admittance signatures and demonstrated the possibility to calibrate with the corrosion rates. Experimental results indicate that SPPS is very sensitive in capturing the changes during the corrosion progression and statistical metric-based method can identify the phases of corrosion. The identified structural parameters (stiffness, mass, and damping) are found to be effective in assessing the material degradation under corrosion in a realistic manner. Hence, it can be concluded that the SPPS via EMI method can be effectively employed in real-life scenarios for diagnosing the PSC structures subjected to corrosion.