U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
| REPORT |
| This report is an archived publication and may contain dated technical, contact, and link information |
 |
| Publication Number: FHWA-HRT-15-079 Date: June 2018 |
Publication Number: FHWA-HRT-15-079 Date: June 2018 |
PDF Version (6.04 MB)
PDF files can be viewed with the Acrobat® Reader®
This report presents findings on a corrosion study related to the corrosion resistance of eight types of metallic dowel bars. The accelerated laboratory corrosion testing was performed using seven small-scale concrete slabs that simulated typical concrete pavements for 452 d of a modified Southern Exposure followed by a detailed autopsy of the extracted bar samples. The best corrosion performance was achieved by type 316L solid stainless steel (SS) dowel bars. Three types of stainless steel–clad bars also exhibited superior corrosion resistance. The epoxy-coated dowel bars performed well and behaved similarly to the SS bar types despite varying degrees of coating delamination and localized corrosion originating from some of the artificial coating defects.
The target audience of this report is State transportation departments, city and county engineers, pavement researchers, and consulting firms.
Cheryl Allen Richter, P.E., Ph.D.
Director, Office of Infrastructure
Research and Development
Notice
This document is disseminated under the sponsorship of the U.S. Department of Transportation (USDOT) in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document.
The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this report only because they are considered essential to the objective of the document.
Quality Assurance Statement
The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.
Technical Report Documentation Page
| 1. Report No.
FHWA-HRT-15-079 |
2. Government Accession No.
|
3 Recipient's Catalog No.
|
||
| 4. Title and Subtitle
Laboratory Evaluation of Corrosion Resistance of Various Metallic Dowel Bars |
5. Report Date
June 2018 |
|||
| 6. Performing Organization Code
|
||||
| 7. Author(s)
Seung-Kyoung Lee |
8. Performing Organization Report No.
|
|||
| 9. Performing Organization Name and Address
SK Lee & Associates, Inc. Rutgers, The State University |
10. Work Unit No. (TRAIS)
Center for Advanced Infrastructure and Transportation (CAIT) |
|||
| 11. Contract or Grant No.
DTFH61-08-C-00005 |
||||
| 12. Sponsoring Agency Name and Address
Office of Infrastructure Research and Development |
13. Type of Report and Period Covered
Final report; January 2006–August 2015 |
|||
| 14. Sponsoring Agency Code
HRDI-60 |
||||
| 15. Supplementary Notes
The Federal Highway Administration Technical Contact is Donald Becker (HRDI-10) and the Contracting Officer’s Representative is R. Zobel (HRDI-30). |
||||
| 16. Abstract
This report presents corrosion study findings related to corrosion resistance of eight types of metallic dowel bars. The accelerated laboratory corrosion testing was performed using seven small-scale concrete slabs that simulated typical concrete pavements for 452 d of a modified Southern Exposure followed by a detailed autopsy of the extracted bar samples. The weekly Southern Exposure cycles consisted of a 4-d wetting cycle in 15 weight percent chloride solution at 75°F and a 3-d drying cycle at 100°F. The best corrosion performance was achieved by type 316L solid stainless steel (SS) dowel bars. Three types of stainless steel–clad (SC) bars also exhibited superior corrosion resistance. The epoxy-coated (EC) dowel bars performed well and behaved similarly to the SS bar types. However, the autopsied EC dowel bars revealed varying degrees of coating delamination, and localized corrosion originated from some of the artificial coating defects. Despite this problem, EC dowel bars were able to suppress corrosion activities because of the shielding role of the coating, even disbonded EC dowel bars, against corrosion current. As expected, the worst corrosion performance was observed with the uncoated carbon steel dowel bars. Most of them produced the corrosion-induced concrete cracks. The hot-dip galvanized and zinc-clad dowel bars are classified as the second worst performance group. Even though the zinc-coating layers performed well as the sacrificial cathodic protection systems for the bare steel exposed at the artificial defect sites, the consumption rates of the zinc mass were too excessive, leading to the premature depletion of the zinc layers in the areas with elevated chloride concentration. Therefore, these zinc-based dowel bars are recommended only for infrequently salted roadways and mild service conditions. For major roadways, where repairs and/or traffic disruption are not feasible, high grades of solid SS dowel bars are recommended, even though this means very high initial costs. Considering the unavailability of the SC bars and the good performance of EC dowel bars at a much lower price, it is recommended that high-quality EC dowel bars be continuously used in the majority of the major roadways subject to heavy deicing salts provided that damage touchups and stringent quality assurance/quality control practices are implemented in the field to minimize initial coating defects until they are buried in concrete. |
||||
| 17. Key Words
Corrosion, corrosion resistant metallic dowel bars, chloride threshold, corrosion initiation, corrosion propagation, autopsy, accelerated corrosion testing |
18. Distribution Statement
No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161. |
|||
| 19. Security Classification (of this report) Unclassified |
20. Security Classification (of this page) Unclassified |
21. No. of Pages
92 |
22. Price
|
|
| Form DOT F 1700.7 (8-72) | Reproduction of completed page authorized |
