Developments in Intelligent Monitoring of Concrete Structures

Deterioration in concrete comprises an initiation period and a propagation period. The initiation period is characterised by changes that occur within the concrete in response to the exposure environment and continues until a stage is reached when damage begins to propagate. The propagation period begins at a point in time defined when a particular event occurs (e.g. loss of steel passivity due to chloride ingress) and continues until a specified limit state is reached. The initiation and propagation stages of a deterioration process result from a complex interaction of physical, chemical and electrochemical phenomena. Prediction of the field performance of reinforced concrete thus requires numerous data inputs, in particular, the response of the cover-zone concrete (covercrete) to the changing ambient environment in the vicinity of a specific structural element or part of a structure.