Updating of the corrosion degree based on visual data combined with strain or modal data

Many existing bridges are reaching the end of their technical service life. To estimate the remaining lifetime of reinforced concrete structures, it is important to assess the parameters of the corrosion process (i.e. parameters governing the corrosion propagation, but also parameters of the chloride or carbonation ingress). The level of corrosion and its spatial distribution can be inferred from strain data under static loading or modal data. In addition, information from visual inspections is often available as well, although not often used to quantify the level of corrosion. In this work, it is investigated how visual inspections can supplement the strain and/or modal data and provide information on corrosion parameters. The developed framework is applied to a simply supported beam subjected to corrosion.