HALF-CELL POTENTIALS AND THE CORROSION OF STEEL IN CONCRETE
THE HALF-CELL POTENTIAL OF STEEL EMBEDDED IN CONCRETE SPECIMENS IN LABORATORY TESTS WAS PERIODICALLY MEASURED AND RELATED TO THE VISUAL OBSERVATION OF CONCRETE CRACKING. IT WAS OBSERVED THAT, WHEN THE HALF-CELL POTENTIAL VALUES WERE MORE NEGATIVE THAN -0.45 V TO THE SATURATED CALOMEL ELECTRODE, 60 PERCENT OF THE REINFORCED CONCRETE BLOCKS WERE CRACKED FROM THE CORROSION OF THE STEEL. AT VALUES BETWEEN -0.27 AND -0.42 V, THE STEEL WAS CORRODING BUT NOT ALWAYS ENOUGH TO CAUSE CONCRETE CRACKING. IN CRACKED CONCRETE, THE MAXIMUM HALF-CELL POTENTIAL OF THE STEEL WAS MEASURED TO BE -0.59 V. IN ADDITION TO THE LABORATORY TESTS ON SMALL SPECIMENS, A PROTOTYPE-SIMULATED BRIDGE DECK WAS EXPOSED OUTDOORS TO PERIODIC WETTING AND DRYING OF A CHLORIDE SALT SOLUTION, AND HALF-CELL POTENTIALS WERE MEASURED BY USING VARIOUS TECHNIQUES. IT IS SHOWN THAT, ONCE CORROSION BEGINS, THE MEASUREMENTS WILL SHOW THE POTENTIAL GRADIENTS OF THE RESULTING CORROSION CURRENTS IRRESPECTIVE OF THE TECHNIQUE USED TO OBTAIN THEM. HOWEVER, THERE WAS A SIGNIFICANT DIFFERENCE IN THE LEVEL OF THE POTENTIALS, AND THAT LEVEL WAS CLEARLY ASSOCIATED WITH THE METHOD OF ELECTRICAL MEASUREMENT.
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Availability:
- Find a library where document is available. Order URL: http://worldcat.org/isbn/0309021634
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Supplemental Notes:
- Sponsored by Committee on Corrosion. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
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Authors:
- Stratfull, Richard F
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Conference:
- 52nd Annual Meeting of the Highway Research Board
- Location: Washington District of Columbia, United States
- Date: 1973-1-22 to 1973-1-26
- Publication Date: 1973
Media Info
- Media Type: Print
- Features: Figures; References; Tables;
- Pagination: pp 12-21
- Monograph Title: Corrosion, concrete and quality control
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Serial:
- Highway Research Record
- Issue Number: 433
- Publisher: Highway Research Board
Subject/Index Terms
- TRT Terms: Bridge decks; Brines; Chlorides; Concrete; Corrosion; Cracking; Electric potential; Laboratory tests; Material reinforcement; Materials science; Reinforced concrete; Sodium chloride; Sodium chloride
- Uncontrolled Terms: Concrete cracking
- Subject Areas: Highways; Materials;
Filing Info
- Accession Number: 00214279
- Record Type: Publication
- ISBN: 0309021634
- Files: TRIS, TRB
- Created Date: Dec 22 1973 12:00AM