Anodes and adhesives tested for bridges

Citation

(2001), "Anodes and adhesives tested for bridges", Anti-Corrosion Methods and Materials, Vol. 48 No. 1. https://doi.org/10.1108/acmm.2001.12848aab.003

Anodes and adhesives tested for bridges

Anodes and adhesives tested for bridges

Keywords: Cathodic protection, Concrete

The US Department of Transportation's Federal Highway Administration (FHWA) recently concluded a study involving the development and testing of a zinc anode/hydrogel system for galvanic cathodic protection (CP) of reinforced concrete bridges.

Reinforced concrete bridge decks and substructures are susceptible to corrosion from deicing salts and seawater, which can pass through concrete pores and attack the steel. Although CP has proved to be an effective means of protecting these structures. the FHWA initiated its study because some CP installations were experiencing problems.

Most of the problems were caused by improper maintenance on the complex impressed-current CP systems that typically were used. Although galvanic CP systems are simpler and require less maintenance, the anodes often do not provide enough current. The study was aimed at developing and testing anodes and conductive adhesives that could provide sufficient current to protect reinforced concrete structures.

The researchers developed a zinc anode/hydrogel conductive system and installed it on three bridges in Florida and Oregon. The galvanic CP systems were monitored for three years. The study found that the system was easy to install and provided adequate protective current flow. More field experience will be necessary to determine the anodes' long-term performance.