Experimental Study to Characterize a Magneto-Functional Technology vs. Corrosion in Reinforced Concrete Structures

Summary In this paper, we propose to show the results of an experimental study to validate a concept of a new Structure Health Monitoring (SHM) sensor dedicated to the detection of aggressive agents in reinforced concrete structures. This sensor, aimed to be embedded in cover concrete, is composed with a permanent part, that acts as a reference magnetic source, coupled with a magneto-functional material (or reactive part), directly in touch with aggressive agents (chlorides in our case) that can cause its corrosion. As a function of its corrosion rate, the reactive part can filter differently a magnetic non destructive observable measured from the permanent part. We chose to present measurements of the magnetic non destructive observable of sensors with reactive parts in their initial and corroded states. The influence of reactive part’s thickness and corrosion rate (based on relative mass loss of reactive part) are shown. Variations of the magnetic observable can be correlated with mass loss of reactive part. These results allowed to draw a empirical calibration curves providing a possibility to monitor reactive part’s corrosion rate. These informations could be used to detect the presence of aggressive agents before they reach rebars.