PCCP Deterioration Rate Detection with AET
Acoustic Emission Testing (AET) establishes the level of active distress in individual prestressed concrete cylinder pipes (PCCP). This unique patented system uses sensors to measure the number of wire related acoustic events that occur along a monitored pipeline over a set period of time. AET identifies pipeline distress while the line is in service, during pressure tests, during the filling of the pipeline and during the pressuring of the pipeline.
How it works:
During manufacturing, PCCP is reinforced by spirally wrapping high strength steel wire around a concrete cylinder. Over time PCCP tends to degrade during normal use, which could lead to these wires failing. If any wires break or slip, the stored energy within the prestressing wires is released.
Much of this energy is in the form of sound energy, which propagates through the pipe core and into the column of water within the pipe. If the deterioration persists, the prestressing wire continues to break and slip, releasing more energy in a series of discrete events that can be detected by an AET system.
The location of the wire related event is calculated using the precise times that the event arrived at the surrounding sensors and the speed of sound in water.
AET Advantage:
- Make informed decisions on when and how to conduct further condition assessment programs.
- Prioritize capital expenditures by enacting a selective repair and replacement program that is based on current distress levels.
- Manage the inherent risks of operating pressurized concrete pipe. A long-term monitoring program enables an operator to establish the rate of infrastructure deterioration.
- Accurately value pipeline assets on there current condition, thereby complying with legislative requirements.
AET Applications:
- All prestressed concrete cylinder pipe (PCCP) pipelines.
- Pipe diameters from 16" to 252".
- Systems available for water and wastewater pipeline inspection.
- Strategic Risk Monitoring of known distressed pipes.
- Monitor the impact that filling and pressurizing the pipeline has on the prestressing wires.
Complementing Services:
- Remote Field Transformer Coupling (RFTC) to accurately determine the condition of individual pipe lengths to help prioritize repair and replace programs.
- PPIC pipeline GIS software to store and quickly display condition assessment results to help optimize asset management.
- Remote Transient Pressure Monitoring (RTPM) to record the variation of pressures within a pipeline caused by sudden changes in velocity of the liquid, known as a “surge” or “water hammer”.