Under FHWA Demonstration Project No. 34, "Cathodic Protection for Reinforced Concrete Bridge Decks," a slotted cathodic protection system was installed on the ES ramp in the Woodinville Interchange during the summer of 1985. The slotted cathodic protection system involves sawing 3/4" slots longitudinally in the existing deck at one-foot centers. Platinum wire or carbon strand wire is placed in the cut slots first and then conductive polymer is filled in the slots. Electric power from a rectifier supplies current to the wire and conductive polymer. The current then flows to the top mat reinforcing steel, giving the steel protection from further corrosion.
The objective of the demonstration project was to familiarize the Washington State DOT with this new technology. This objective was fulfilled.
Some problem areas with the system were identified during the work:
These problems need to be overcome to obtain a better quality product.