Inductive Scan Imaging Technique in Detecting and Visualizing Corrosion for Large Scale Pre-Stressed Concrete Cylinder Pipes

No single method for monitoring Pre-stressed Concrete Cylinder Pipes (PCCP) using either standard corrosion monitoring systems or non-destructive techniques can accurately determine the onset of corrosion. This paper investigates the capability of the Inductive Scan Imaging Technique as a new single non-destructive tool in identifying and visualising corrosion of pre-stressed wires embedded in concrete and distinguishing between corrosion of varying severity, position and size. The future application and use of the new technique in determining the effect of cathodic protection (CP) on the performance of passivated, corroded and split pre-stressed wire is also discussed. The paper also discusses the advantages and limitations of the various available conventional monitoring techniques such as Static, Close Interval Potential Survey and polarization coupons to measure corrosion rates and non-destructive inspection methods that can identify distressed pipe areas.