Hazard Mitigation of Water Mains by Means of Immersed Active/Passive Inspection Systems

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

This research project will study the development of a hybrid laser/immersion transducers system suitable for inspecting fresh water mains as well as other underwater structures. The research aims to detect normally invisible cracks on the interior walls of the underground mains that initiate disruptions in the water supply systems causing widespread distress in local communities and businesses. The crack detection concept is based on the hypothesis that underwater laser pulses are able to generate stress waves along the axial and the circumferential directions of the pipe that can be detected by an array of immersion transducers devoted to the detection of these stress waves. It is proposed to collect adequate data to provide full pipeline coverage along the pipe length to minimize false positives/negatives. The project will develop a trenchless technology with the design of a prototype that may be used on an underwater vehicle to inspect pipes from the inside without service disruption. These goals shall be accomplished by using guided ultrasonic waves generated and detected from inside the pipe using non contact methods and advanced digital signal processing of the generated and detected wave data to detect crack anomalies underneath the interior walls of the pipes. Besides the importance of the research results to the scientific community, the proposed research will have a significant impact on the inspection approaches that are used for underwater structures in civil and military applications as the system proposed to inspect freshwater mains from the inside can be also employed to monitor large underwater structures. This research will provide multidisciplinary and advanced education and training to students participating in the project. The research is expected to lead to a patentable technology with potential marketing opportunities. The research results will be broadly disseminated through publication of research results in technical journals and through the presentation at national and international conferences and professional meetings.