Extraction of Reflected Wave Delay Time for the Location of Buried PE Pipeline

Polyethylene (PE) pipes have been widely employed in the construction of medium and low-pressure gas and water pipeline networks. However, the lack of accurate underground pipeline locations and detection instruments leads to repeated occurrences of pipeline safety accidents during construction. To address this issue, this article proposes an acoustic method for detecting buried PE pipelines by extracting the delay time of reflected waves. First, the propagation of acoustic waves at the pipe-soil interface is analyzed, followed by the introduction of a method for extracting the delay time of reflected waves to locate buried PE pipelines. Numerical simulations are subsequently presented to examine the influence of the spacing between the P-wave detector and the source on the extraction of delay time, and hence, the accuracy of the positioning algorithm. Finally, experiments are carried out at test sites with and without buried pipes at a burial depth of 0.9 m. The test results demonstrate that the proposed pipeline detection method effectively determines the presence of pipelines. The maximum plane positioning error for multiple survey lines is found to be 0.188 m, indicating the superior performance of the proposed method compared to existing acoustic pipeline detection methods. This study confirms the feasibility of the proposed pipeline detection method for buried PE pipelines, potentially contributing to the development of acoustic instruments for locating urban buried nonmetallic pipelines.