Next Steps in the Evolution of an Acoustic Emission Testing System

A number of water utilities have successfully used Acoustic Emission Testing (AET) to locate active distress in Prestressed Concrete Cylinder Pipe (PCCP). However, in conducting an AET monitoring program, questions often arise as to: the maximum spacing allowed between units; the minimum duration of the monitoring period; and the system's ability to distinguish between wire breaks and wire slips. These questions determine the value of AET in a condition-based asset management program. To address these questions, scientific and fact-based studies were conducted. This paper discusses these studies using extensive analysis of AET field results. It suggests how water utilities can conduct AET programs more cost-effectively through knowledge of the maximum spacing interval for acoustic sensors and the minimum monitoring time required for pipes in different stages of distress.