Uncoated reinforcing steel in concrete

Test method for porosity in gold platings on metal substrates by gas exposures Test method for half-cell potentials of uncoated reinforcing steel in concrete Method for detection of copper corrosion from petroleum products by the copper strip tarnish test... 

ASTM C 876-91, Standard Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete, American Society for Testing and Materials, Philadelphia, PA, USA, 1991, pp 437-442. 

Corrosion tests that are performed on lollipops are corrosion potential readings as described in ASTM C 876 (Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete), polarization resistance as described in ASTM G 59, using IR correction [3,9], and EIS [9]. Specimens are broken open to visually examine the bars for confirmation of the electrochemical results, and chloride analyses are performed. The chloride analysis correlates the chloride content to the corrosion activity. 

ASTM C 876, Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete... 

Standard Test Method for Mercurous Nitrate Test for Copper and Copper Alloys Standard Specification for Cellulosic Fiber (Wood-Base) Loose-Fill Thermal Insulation Standard Test Method for Half-CeU Potentials of Uncoated Reinforcing Steel in Concrete Standard Test Method for Detection of Copper Corrosion from Petroleum Products by the Copper Strip Tarnish Test... 

Coated reinforcement MacroceU formation may be important in the case of epoxy-coated rebars (Section 15.4) in chloride-contaminated concrete if there are defects in the coating and the coated bars are electricaUy connected with uncoated passive steel bars in deeper parts of the structure. Small anodic areas are created at the defect points of coated rebars in contact with chloride-contaminated concrete, while the uncoated passive rebars provide a cathodic surface of much greater size. In these situations the macroceU can result in considerable anodic current densities and can significantly accelerate the attack on corroding sites. This is why coated rebars should be electrically isolated from uncoated bars. 

Very often steel sheet pilings exist in conjunction with steel-reinforced concrete structures in harbors or locks. If cathodic protection is not necessary for the reinforced concrete structure, there is no hindrance to the ingress of the protection current due to the connection with the steel surfaces to be protected. The concrete surface has to be partly considered at the design stage. An example is the base of the ferry harbor at Puttgarden, which consists of reinforced concrete and is electrically connected to the uncoated steel sheet piling. 

To date, the most frequent application of Ebonex (named for its black color) has been in cathodic protection, especially of the steel rods used to reinforce concrete [1]. There is an extensive literature oti Ebonex coated with various other materials (noble metals, carbon, lead dioxide), whose deposition is favored by Ebonex s high overpotential for hydrogen and oxygen evolution. Applications for coated Ebonex include batteries, fuel cells, and dechlorination of chlorinated pollutants [2], but the focus of this article is the use of uncoated Ebonex as an electrode material for electrolysis of pollutant substances, most often for electrochemical oxidation. 

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