Acoustic emissions monitoring of welded structural members partially embedded in concrete Academic Article in Scopus uri icon

abstract

  • Copyright © SHMII 2019. All rights reserved.Direct inspection of welded structural elements embedded in concrete is, in most cases, not possible and, when necessary, it requires partial demolition for direct inspection. Gamma or X rays are not both inspection alternatives because of concrete thickness and steel reinforcing bars. This is the case of the upper anchoring elements of a cable-stayed bridge, which failed due to a defective weld and fatigue growth. To evaluate the weld of the remaining 111 anchoring elements the acoustic emissions technique was used to identify the presence of cracks and to estimate the risk of fatigue failure; and in a long term monitoring, to evaluate the effect of fatigue on defect growth. The condition of the welds it was evaluated through a Severity Index, which was defended from the AE Duration-Amplitude curves. Limits for defect sizes were defined from this index and from direct ultrasonic inspection of two pre-selected welds where concrete was demolished. Results show the potential of this method on monitor the weld condition of these elements and their fatigue evolution for future maintenance.

publication date

  • January 1, 2019