As in many other areas also the construction industry requests more and more methods of online-monitoring
of corrosion related values. Monitoring the reinforcement corrosion, which is the main cause for
damages or early rehabilitation measures, promises a subjectively higher safety feeling to unexpected
lack of usefulness or sudden need for rehabilitation. In the paper a survey of methods and sensors for
corrosion monitoring in reinforced concrete structures are presented.
Basing on extensive tests as well as in the laboratory as on-site performed in many research projects
during the last 10 years different devices and methodologies are described regarding their special features
and application areas. Hereby techniques using portable equipments and permanently installed
systems are shown. The permanent systems are divided into systems installed during construction of
new structures and post-mounted devices for installation in existing structures.