Application of Computational Modeling to Predict the Effectiveness of CP on a PCCP Transmission Pipeline

PCCP is a rigid pipe designed to take optimum advantage of the tensile strength of steel and of the compressive strength and corrosion inhibiting properties of concrete and is frequently used for water transmission. Prestressed Concrete Cylinder Pipe (PCCP) consists of a steel cylinder embedded in a concrete core, which is helically wrapped with high-strength, hard-drawn wire after curing. The wire is embedded in thick cement slurry and coated with a dense cement mortar.

While the cement mortar and additional coatings initially protect the pre stress wires from corrosion, over time chlorides can diffuse into the mortar and reach the wires. Therefore PCCP transmission pipelines are also protected by CP systems to mitigate the risk of corrosion damage to the wires.

This paper describes a computer modelling study which was designed to determine the protection provided by an ICCP system, to evaluate different design options and to optimise the design. Results will be presented showing the model predictions for the different cases considered.

Keywords

Cathodic Protection, PCCP, Computer modelling, Reinforced Concrete