Determining Localized Anode Condition to Maintain Effective Corrosion Protection
Thermal sprayed zinc anodes used for impressed current cathodic protection of reinforced concrete deteriorate over time. Two different technologies, ultrasound and electrical circuit resistance combined with water permeability, were investigated in the laboratory to determine whether they were feasible methods for estimating anode condition. The ultrasonic method was unable to detect a reflected acoustic signal from zinc-on-concrete specimens due to scattering of the signal within the samples. Circuit resistance was shown to increase with the electrochemical age of the specimens, but the resistance trend did not correlate with the bond strength trend at later ages. The aged specimens were fairly impermeable to water infiltration presumably due to build up of reaction products in the porosity. Consequently, a method of using resistance measurements combined with water infiltration to determine anode condition was not successful. It was shown that the permeability improved if the surface was mechanically perturbed such as creating a pin hole. Improving permeability by penetrating the surface could have ramifications for improving anode performance.
- Record URL:
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Corporate Authors:
Oregon State University, Corvallis
School of Chemical, Biological and Environmental Engineering
Corvallis, OR United States 97331Oregon Department of Transportation
Research Section, 200 Hawthorne Avenue, SE, Suite B-240
Salem, OR United States 97301-5192Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC United States 20590 -
Authors:
- Nguyen, Vinh
- Meuli, Josh
- Brooks, Bill
- Jansen, Henri
- Westall, John
- Koretsky, Milo
- Publication Date: 2010-1
Language
- English
Media Info
- Media Type: Web
- Edition: Final Report
- Features: Appendices; Figures; Photos; References; Tables;
- Pagination: 134p
Subject/Index Terms
- TRT Terms: Anodes; Bond strength (Materials); Cathodic protection; Corrosion protection; Deterioration; Permeability; Reinforced concrete bridges; Resistance (Electricity); Ultrasonic detectors; Zinc
- Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation; I61: Equipment and Maintenance Methods;
Filing Info
- Accession Number: 01154218
- Record Type: Publication
- Report/Paper Numbers: FHWA-OR-RD-10-11
- Contract Numbers: SPR 653
- Files: TRIS, ATRI, USDOT, STATEDOT
- Created Date: Apr 12 2010 4:26PM