Development, Testing and Field Application of Metallized Cathodic Protection Coatings on Reinforced Concrete Substructures

摘要

The report presents laboratory and field studies relating to the technology, materials and instrumentation used to develop and test a cathodic protection system for reinforced concrete substructures (vertical surfaces). Laboratory evaluations of fifteen conductive paints and metallized coatings were performed to determine the coating bond strength, resistivity, weatherability, and consumption rate during cathodic protection current delivery. Instant-off and polarization shift surveys were also conducted. The application and results of 6.1 years of laboratory and field testing, which included 3.6 years of monitoring an impressed current cathodic protection system using metallized zinc and Sprababbitt A as the distribution anodes, are documented. The system was applied to two reinforced concrete columns of a bridge substructure in a marine environment in the San Francisco Bay. The system has been operating since August 1983. A sample specification for applying metallized zinc to cathodically protected reinforced concrete substructures is also included.