Damage analysis of stress corrosion test of pretensioning steel strands by ae monitoring

In the present work the application of acoustic emission technique has been proposed as a tool for theevaluation of corrosion processes occurring under SCC conditions on prestressing steel strands. To simulatethe possible corrosive environment under service conditions experimental tests were performed with differentelectrolytes and electrochemical conditions (open circuit potential, cathodic and anodic polarisation). The useof multi-variable techniques, coupled to a classic statistical approach, has permitted to discriminate separatedclusters in the population of the acquired AE signals related with specific damage events. Thereby theproposed approach allowed to create corrosion maps able to classify both global and punctual degradationphenomena. In particular different areas of the maps were related to the different corrosion mechanismsexperimentally observed during the SCC tests