On-site Corrosion Monitoring - Reliability

The European countries have a great number of reinforced concrete bridges and many of them are suffering from corrosion. Prior to define a repair strategy, a precise and reliable diagnosis of the corrosion state of the reinforcing bars is mandatory. In order to carry out this inspection, many challenges remain especially for the RC structures exposed to a marine environment. The assessment strategy is based on the choice of Non Destructive Techniques taking into account their precision, location, number of measurements, the environmental conditions and duration. Currently, more empirical approaches are used by structure's owners and we propose to implement statistical methods as well as data mining for a more reliable and optimal diagnosis. Within the DeCoF-Re project, the diagnosis tools and the evaluations made afterwards are established from data obtained on different piers of a real bridge, based on NDT such as visual inspection of the degradations, rebar's localization, half-cell potential mapping, electrical concrete resistivity mapping and corrosion rate measurements performed in 2015. The first results are presented. They concern the effect of environment on the reliability of diagnosis. An additional durability study based on the analysis of durability indicators (such as chloride profiles) will be conducted in 2016.