Effect of the paste–anode interface under impressed current cathodic protection in concrete structures
Journal article, 2018

Impressed current cathodic protection (ICCP) is a powerful method to prevent and stop corrosion of steel in concrete structures. To evaluate the long-term effect of ICCP, accelerated tests have been adopted using high current densities. A carbon fiber reinforced polymer mesh was introduced as anode. The presented research focused on the changes at the paste-anode interface as a consequence of applying current. The treated samples were characterized by various techniques.

Calcium dissolution was found with an average thickness of 0.34 mm around the anode after charges of 6*10^6 C/m2 were applied, equivalent to applying 4 mA/m2 of anode surface for 30 years. Calcium dissolution resulted in a white zone around the anode, where the calcium silica ratio was lowered and almost no crystal phase was observed. NMR results show clear Q3 and Q4 peaks in the white zone, which contained extended branched and networked structures of hardened cement paste. An increased resistance caused by the formation of the white zone may eventually make the system fail because of insufficient current densities. CFRP has been proven suitable for ICCP application even at a current density of 4 A/m2 of anode surface.

calcium dissolution

cathodic protection

accelerated test

CFRP anode

paste–anode interface

microstructure

Author

Emma Zhang

Chalmers, Architecture and Civil Engineering, Building Technology

Luping Tang

Chalmers, Architecture and Civil Engineering, Building Technology

Diana Bernin

University of Gothenburg

Helen Jansson

Chalmers, Architecture and Civil Engineering, Building Technology

Materials and Corrosion - Werkstoffe und Korrosion

0043-2822 (ISSN) 1521-4176 (eISSN)

Vol. 69 8 1104-1116

Development of sustainable electrochemical corrosion protection systems for reinforced concrete structures (DOSECOPS)

European Commission (FP7), 2012-07-01 -- 2016-06-30.

Covercrete with hybrid functions - A new approach to sustainable reinforced concrete structures with low cement content

Formas, 2012-03-15 -- 2015-03-15.

Areas of Advance

Building Futures (2010-2018)

Materials Science

Subject Categories

Infrastructure Engineering

Materials Chemistry

Other Chemistry Topics

Composite Science and Engineering

Corrosion Engineering

Condensed Matter Physics

Infrastructure

Chalmers Materials Analysis Laboratory

DOI

10.1002/maco.201709908

More information

Latest update

8/31/2018