Acoustic emission use for stress corrosion cracking detection in prestressing strands of bridge structures
Résumé
Many ageing bridges do not benefit today from the integration of real-time monitoring methods and a potential risk of collapse exists. For prestressed bridges, a specific pathology, i.e. stress corrosion cracking (SCC) assisted by hydrogen of prestressing strands can lead to a severe degradation of these structures. Due to the limited accessibility to prestressing strands, AE seems to be particularly adapted to monitor SCC. The aim of this research is to detect SCC damages with AE on real-like structures. Preliminary works have allowed the optimisation of the structure instrumentation. Results show that AE are strongly attenuate when strands are surrounded by cement grout but an acoustic activity is recorded on each sensor during the accelerated corrosion test.