In 1994, the Strategic Highway Research Program (SHRP) published results from a research study on freezing and thawing of concrete, in which a number of concretes containing 2.5 to 3 percent total air performed adequately in freeze-thaw tests. These results seemed surprising in light of common minimum specification limits of 4 to 6 percent. The work reported here began as a followup study to the SHRP work, an attempt to corroborate the earlier results.
This report describes a laboratory investigation of the behavior of concrete with “marginal” air void systems, in which the air content and other air void system parameters do not consistently meet commonly accepted thresholds for freeze-thaw durability. Some of the concretes did provide good durability-but others did not. The type of air-entraining admixture played a major role in performance. In addition to measuring air-void parameters by the linear traverse technique, special programmed equipment at Turner-Fairbank Highway Research Center (TFHRC) was used to measure and record each individual chord length across the air voids traversed. The air-void chord length distributions are presented and analyzed in this report. The research that is the subject of this paper was funded by the Federal Highway Administration (FHWA) and conducted entirely at FHWA’s TFHRC.
The results of this research will be of interest to engineers involved in the construction and acceptance of both concrete pavements and structures built in climates with below-freezing temperatures. The report will also be of interest to concrete researchers studying the factors affecting concrete durability.
Gary L. Henderson
Director, Office of Infrastructure
Research and Development
This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation.
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.
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.
1. Report No.
FHWA-HRT-06-117 |
2. Government Accession No.
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3. Recipient's Catalog No.
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4. Title and Subtitle
Freeze-Thaw Resistance of Concrete With Marginal Air Content |
5. Report Date
December 2006 |
6. Performing Organization Code
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7. Author(s)
Jussara Tanesi and Richard Meininger |
8. Performing Organization Report No.
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9. Performing Organization Name and Address
FHWA Office of Infrastructure Research and Development
6300 Georgetown Pike
McLean VA 22101 |
10. Work Unit No. (TRAIS)
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11. Contract or Grant No.
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12. Sponsoring Agency's Name and Address
Office of Research, Development, and Technology
Federal Highway Administration
6300 Georgetown Pike
McLean, VA 22101-2296 |
13. Type of Report and Period Covered
Final report
2001-2004 |
| 14. Sponsoring Agency's Code |
15. Supplementary Notes
Point of contact at TFHRC (FHWA) is Richard Meininger, HRDI-11. |
16. Abstract
Freeze-thaw resistance is a key durability factor for concrete pavements. Recommendations for the air void system parameters are normally: 6 ± 1 percent total air, and spacing factor less than 0.20 millimeters. However, it was observed that some concretes that did not possess these commonly accepted thresholds presented good freeze-thaw resistance in laboratory studies.
This study evaluated the freeze-thaw resistance of several “marginal” air void mixes, with two different types of air-entraining admixtures (AEA)-a Vinsol resin and a synthetic admixture. This study used rapid cycles of freezing and thawing in plain water, in the absence of deicing salts.
For the specific materials and concrete mixture proportions used in this project, the marginal air mixes (concretes with fresh air contents of 3.5 percent or higher) presented an adequate freeze-thaw performance when Vinsol resin based air-entraining admixture was used. The synthetic admixture used in this study did not show the same good performance as the Vinsol resin admixture. |
17. Key Words
freeze-thaw, Vinsol resin, synthetic, air-entraining admixture, marginal air. |
18. Distribution Statement
No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161. |
19. Security Classif. (of this report)
Unclassified |
20. Security Classif. (of this page)
Unclassified |
21. No. of Pages
93 |
22. Price
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