Impedance-based wireless debonding condition monitoring of CFRP laminated concrete structures

Carbon fiber reinforced polymer (CFRP) laminated concrete structures are used widely in a range of engineering fields because of their many advantages. However they always carry the risk of structural collapse initiated from the debonding conditions that might occur between the CFRP and concrete surface. This study employed an electro-mechanical impedance-based wireless structural health monitoring (SHM) technique by applying PZT ceramic patches to identify the debonding conditions of a CFRP laminated reinforced concrete beam. In the experimental study, the CFRP-reinforced concrete specimens were fabricated and the impedance signals were measured from the wireless impedance sensor node according to the different debonding conditions between the concrete and CFRP. Cross correlation (CC)-based data analysis was conducted to quantify the changes in impedance measured at the PZT patches due to the debonding conditions. The results confirmed that an impedance-based wireless SHM technique can be used effectively for monitoring the debonding of CFRP laminated concrete structures.