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Corrosion Engineering: Rust Never Sleeps
DP-84 Corrosion Survey Techniques
DP-91 Cathodic Protection (CP) for Reinforced Concrete Structures
DP-91 Cathodic Protection For Reinforced Concrete Bridge Decks
TE-42 Assessment of Physical Condition of Reinforced Concrete Structures
TE-43 Methodologies for Reinforced Concrete Removal, Repair, Protection, and Rehabilitation
    Guide Specifications for Cathodic Protection of Concrete Bridge Decks
    Manual For Corrosion Protection Of Concrete Components In Bridges TE-44 Electrochemical Chloride Extraction from Reinforced Concrete Structures
Corrosion is a natural electrochemical process in which the energy gained in the conversion of iron ore to steel is released in the form of a direct current. The combination of ferrous ions with an electrolyte at the anode produces corrosion products that can occupy up to seven times more volume than the parent steel. In reinforced concrete structural elements, the electrolyte is (concrete containing water and oxygen), which causes the anodic reinforcing steel to corrode. The corrosion products exert detrimental tensile forces in the concrete that produce delaminations, cracking, and subsequent spalls of the structural element.

The combined technology that has resulted from previous FHWA R&D, developments in commercial corrosion hardware, and the SHRP program in concrete and corrosion provides an impressive array of equipment and methods to evaluate corrosion in reinforced concrete, determine the condition of the concrete element, and determine methods for proper repair, rehabilitation, and protection. The next challenge is to evaluate and demonstrate the effectiveness of the technology and to market the successful results to a variety of users.

On structural steel members such as steel girders and floorbeams, a coating system is used to prevent corrosion. However, in severe environments or after long periods of service, the coating system breaks down and corrosion will occur unless the system is repaired or replaced. Continued corrosion of steel members can lead to severe loss of section with detrimental effects on the service capacity and safety of the structure. Older coating systems were formulated with heavy metals, such as lead and chromium, which have been proven to be hazardous to human health. Therefore, the removal, containment, storage, and ultimate disposal of these old coating systems has become an expensive, environmentally complex problem.


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