A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Metallized and conductive coatings as impressed-current anodes for reinforced concrete: Part 1
Steel-reinforcement corrosion can be mitigated by cathodic protection. In order to deliver the protective cathodic current to the rebars, a conductive anode material must be applied to the surface of the protected concrete structure. The performance of two metallized-zinc coating anodes and two conductive paints was investigated, Passcorr Electrocoat 30-86 and Duochem Duodac 85. The former is water-based, while the latter is solvent-based. The coatings were applied according to the manufacturer's instructions using paint rollers. Bond strengths were found to slowly decrease as the current density and the length of the polarization period increased. On the other hand, driving voltages across all coating anodes were found to increase. The increase were significantly more pronounced for the metallized-zinc coating polarized at the higher current density. This could be attributed to the metal oxide products forming at the concrete interface. Evidence of acidification at the anode/concrete interface was only significant for the conductive paints. Acidification was more pronounced at the Duodac 85 conductive coating. There is no explanation for this observation, since oxygen is evolved from both conductive paints when an anodic current is impressed. Breakdown by acid etching of the interface concrete therefore can be assumed to be of minor impact on the adhesion of the conductive coatings under normal operating current densities. Arc-sprayed zinc performed well in this three-year laboratory investigation. It was however outperformed by a solvent-based conductive paint. Arc-sprayed zinc aluminium (85:15) debonded prematurely at higher current density. This alloy is not recommended for use as an impressed-current anode.
Metallized and conductive coatings as impressed-current anodes for reinforced concrete: Part 1
Steel-reinforcement corrosion can be mitigated by cathodic protection. In order to deliver the protective cathodic current to the rebars, a conductive anode material must be applied to the surface of the protected concrete structure. The performance of two metallized-zinc coating anodes and two conductive paints was investigated, Passcorr Electrocoat 30-86 and Duochem Duodac 85. The former is water-based, while the latter is solvent-based. The coatings were applied according to the manufacturer's instructions using paint rollers. Bond strengths were found to slowly decrease as the current density and the length of the polarization period increased. On the other hand, driving voltages across all coating anodes were found to increase. The increase were significantly more pronounced for the metallized-zinc coating polarized at the higher current density. This could be attributed to the metal oxide products forming at the concrete interface. Evidence of acidification at the anode/concrete interface was only significant for the conductive paints. Acidification was more pronounced at the Duodac 85 conductive coating. There is no explanation for this observation, since oxygen is evolved from both conductive paints when an anodic current is impressed. Breakdown by acid etching of the interface concrete therefore can be assumed to be of minor impact on the adhesion of the conductive coatings under normal operating current densities. Arc-sprayed zinc performed well in this three-year laboratory investigation. It was however outperformed by a solvent-based conductive paint. Arc-sprayed zinc aluminium (85:15) debonded prematurely at higher current density. This alloy is not recommended for use as an impressed-current anode.
Metallized and conductive coatings as impressed-current anodes for reinforced concrete: Part 1
Metallisierte und leitfähige Überzüge als Fremdstromanoden für armierten Beton: Teil1
Brousseau, R. (author) / Arnott, M. (author) / Baldock, B. (author)
Corrosion Prevention and Control ; 43 ; 119-130
1996
6 Seiten, 9 Bilder, 2 Tabellen, 8 Quellen
Article (Journal)
English
Metallized and conductive coatings as impressed-current anodes for reinforced concrete
| British Library Online Contents | 1996
Accelerated Testing of Impressed Current Anodes for Reinforced Concrete Structures
| British Library Conference Proceedings | 1994
Thermal Spray Anodes for Impressed Current Cathodic Protection of Reinforced Concrete Structures
| British Library Online Contents | 1999