Experimental Verification of Damage Source Location in Buried Pipelines using Feature Response in the Time-Frequency Domain

Damage to buried pipelines resulting from third-party interference has garnered attention because it can lead to significant leaks owing to ruptures. Given that such incidents often occur suddenly owing to third-party actions, the importance of buried pipeline monitoring becomes paramount for prevention and early response. Acoustic emission localization have been recognized as an effective method for detecting damage sources in structures with restricted access. In this study, we propose a signal processing method based on the feature response in the time-frequency domain to apply acoustic emission localization in noisy environments. We compared the results of the feature response through simulation and experimentally verified its application on in-service buried pipelines. The pipeline is 564 m long and has a diameter of 1200 mm. By attaching vibration accelerometers to both ends, we confirmed the ability to detect impact damages. By observing the feature response, we derived the optimal frequency band without manual frequency analysis. Therefore, we could automatically enhance the signal-to-noise ratio under various noise conditions. Our study yielded an empirical impact damage detection in the in-service pipelines that was in good agreement with the impact location.