Use of 3D Image Data for Leak Detection of in-Service Deteriorated Water Pipeline

Leakage in service pipelines is recognized as a cause of structural failure. This study proposes a non-contact leak detection method with Digital Image Correlation (DIC) based on measuring pipe deformation caused by water hammer pressure with leak information. Strain on the pipe surface is measured without direct access, and deformation characteristics are extracted. Experiments are conducted on both model and in-service pipelines. Frequency-domain features are obtained through Fast Fourier Transform (FFT), and energy attenuation is quantified by damping coefficients. Greater attenuation of water pressure and circumferential strain is observed in leakage cases. The peaks in amplitude spectra are found to be smaller under leakage conditions. The damping coefficients are confirmed to increase as the leakage position becomes closer to the pressure wave source. These findings suggest that leakage-induced energy loss can be effectively evaluated through non-destructive strain measurements. The proposed method has the potential to support pipeline integrity assessment without the use of pressure sensors.