Effects of corrosion on the structural behaviour of existing structures: Corrosion Risk Scenarios and equivalent parameters

Although corrosion has a strong impact on the behaviour of reinforced concrete elements, its effect is seldom investigated by design professionals for the assessment of existing structures and for the design of retrofit interventions. This is also due to the absence of survey protocols enabling the preliminary evaluation of the risks related to corrosion and its impact on the structural behaviour. For this reason, the development of a simplified protocol aimed at evaluating the residual capacity of existing RC struc-tures in order to identify the best intervention strategy is under investigation. Such protocol guides the user in the identification of a ‘Corrosion Risk Scenario’ starting from visual inspection and simple on-site non-destructive tests. Accordingly, equivalent parameters are selected to be adopted for the assess-ment of the structural behaviour over time. In order to characterize each scenario, the effects of corro-sion processes are analysed with tomographic scans and laboratory tests on steel bars extracted from different existing buildings.