Marine environments can be very aggressive and present significant challenges in maintaining key infrastructure from the effects of corrosion. In Florida, thousands of bridges are in coastal areas and are continually, or periodically exposed to saltwater conditions. A clear majority of these bridges were constructed using steel reinforced concrete and are supported by precast pilings situated in saltwater, so for this reason, cathodic protection is a necessary strategy for controlling the effects of saltwater induced corrosion.
Toward the early 1980s, the Florida Department of Transportation (FDOT) began the evaluation of different approaches to control saltwater induced corrosion. Some of these included the use of integral pile jackets, specialty materials for concrete repairs, surface applied coatings and other innovative approaches utilizing galvanic anode technology. One such system was jointly developed with industry partners and sponsored by the Federal Highway Administration (FHWA) using integral pile jackets lined with expanded zinc mesh anodes to apply cathodic protection. This innovative approach provides for the problem of concrete repair while at the same time stopping the on-going process of corrosion both combined in one application. Both laboratory and field trials validated the benefits to this approach and confirmed that the system can mitigate corrosion and extend the useful service life of pilings by more than 20 years.
The purpose of this technical committee report is to provide specifiers, designers, and corrosion control personnel information to control the corrosion of conventional reinforcing steel in hydraulic cement concrete using corrosion inhibiting admixtures.
This report describes several types of materials used as corrosion inhibiting admixtures, their selection and evaluation, their proportioning into freshly mixed concrete, and their effects on fresh and hardening/hardened concrete. Corrosion inhibiting admixtures may help delay corrosion initiation and extend the interval of corrosion propagation.
Population growth in city centers has spurred the expansion and new construction of direct current (DC) powered transit systems throughout the world1. Despite stringent design criteria, quality assurance and quality control (QA/QC) monitored construction practices and ongoing track maintenance, it is a fact that DC stray current will eventually occur and negatively impact buried and/or submerged metallic structures immediately adjacent and within the transit right-of-way (ROW)2. In combination with other methods to reduce stray current such as high track-to-earth (TTE) resistance values and shorter distances between substations, transit agencies are specifying the welding of reinforced steel structures within their purview such as retaining walls and footings, approach slabs, aerial inverts, and bridge abutments to prevent stray current from reducing the design life of surrounding metallic
Reaffirmed (with editorial changes) in 2019. Presents corrosion control guidelines that are applicable to existing atmospherically exposed structures made of concrete conventionally reinforced with carbon steel. These guidelines should be used primarily when repair or rehabilitation is being implemented because of deterioration resulting from the corrosion of steel reinforcement. Includes sections on Periodic Inspection and Routine Maintenance of reinforced-concrete structures (site survey, structural survey, repair options), Assessment of Reinforced Concrete Structures, and Corrosion Control Techniques and Repair Strategy. Corrosion control techniques that are described include surface treatments, removal of concrete, and electrochemical treatments, including ECE, ER, and cathodic protection.
This NACE standard presents guidelines for cathodic protection (CP) of reinforcing steel in buried or submerged concrete structures. These guidelines provide corrosion control personnel with information to control corrosion of conventional reinforcing steel in portland cement concrete structures through the application of CP. The guidelines presented in this standard are limited to CP systems for new or existing buried or submerged reinforced concrete elements.