Acoustic emission monitoring of carbon-fiber-reinforced-polymer bridge stay cables in large-scale testing

This paper presents acoustic emission (AE) monitoring of damage initiation and progression in carbon-fiber-reinforced-polymer (CFRP) stay cables subject to large-scale laboratory tests. The research is part of the University of California, San Diego (UCSD), larger project on the design and construction of a new cable-stayed bridge made of advanced composites. No previous use of AE on large-size CFRP stay cables appears in the literature. Three types of cables of potential use in the UCSD composite bridge were tested at lengths ranging from 5500 mm to 5870 mm. The AE events were monitored to detect damage and provide a qualitative correlation with the type of structural failure. The tests allowed a comparative characterization of the failure behavior of the three types of cables under investigation. An additional study was performed to characterize acoustic attenuation and dispersion phenomena that are relevant to AE testing of large-scale CFRP cables. It is shown that despite their large size, these cables are excellent acoustic wave guides exhibiting very low attenuation. Finally, this study shows promising results for an effective use of in situ AE for health monitoring of these structural components in service.