Title:
Cathodic Protection of a Reinforced
Concrete Bridge Deck
Author(s):
Gerald H. Anderson
Publication:
Concrete International
Volume:
2
Issue:
6
Appears on pages(s):
32-36
Keywords:
asphalts; bituminous concretes; bridge
decks; cathodic protection; chlorides; corrosion; rein-forced
concrete; reinforcing steels; spalling.
DOI:
Date:
6/1/1980
Abstract:
The placement of a cathodic protection system on a restored reinforced concrete bridge deck presented as a means of arresting corrosion of the reinforcing steel in a chloride contaminated environ. . ment. Necessary InsPectrng and testing prior to strutture selectron and restoration are discussed. consideration is given to the system installation and required level of polarized potentials of the top forcing steel for cathodic protection. During the past 2 years of observation, the top mat of reinforcing steel has been polarized at 300 to 400 mV more negative than the static potentials. Corrosometer probe data indicates that further corrosion of reinforcing steel has not occurred since the system was energized. The power required to maintain cathodic protection has averaged about 50 kW per month. As the humidity increases and deck resistance decreases, more cur-rent is required to maintain the set potentials. The constant structure-to-reference potential control has proven convenient and effective in maintaining the desired level of cathodic protection under the ever changing environmental conditions of the deck.