Asphalt Concrete Overlays on Continuously Reinforced Concrete Pavements: Decision Criteria, Tack Coat Evaluation, and Asphalt Concrete Mixture Evaluation

Technical Report Documentation Page 1. Report No. FHWA/TX-05/0-4398-3 2. Government Accession No. 3. Recipient’s Catalog No. 5. Report Date April 2004; Revised February 2005 4. Title and Subtitle Asphalt Concrete Overlays on Continuously Reinforced Concrete Pavements: Decision Criteria, Tack Coat Evaluation, and Asphalt Concrete Mixture Evaluation 6. Performing Organization Code 7. Author(s) Manuel Trevino, Seong-Min Kim, Andre Smit, B. Frank McCullough, Yetkin Yildirim 8. Performing Organization Report No. 0-4398-3 10. Work Unit No. (TRAIS) 9. Performing Organization Name and Address Center for Transportation Research The University of Texas at Austin 3208 Red River, Suite 200 Austin, TX 78705-2650 11. Contract or Grant No. 0-4398 13. Type of Report and Period Covered Technical Report 9/2002-8/2003 12. Sponsoring Agency Name and Address Texas Department of Transportation Research and Technology Implementation Office P.O. Box 5080 Austin, TX 78763-5080 14. Sponsoring Agency Code 15. Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. 16. Abstract This report presents the research undertaken within two areas of study of thin asphalt concrete (AC) overlays to rehabilitate continuously reinforced concrete pavements (CRCP). The first one is the development of a decision tree for the project selection of a rehabilitation of this kind. The second area is the testing of tack coats and AC mixtures for its use in AC overlays. Within the first area, several decision criteria, based on the functional and structural characteristics of the existing pavement, were developed to evaluate the technical suitability of AC overlays on CRCP. These criteria are, namely, a profile criterion, based on the remaining life concept and on the formulation of a dynamic load factor; a condition survey criterion, which utilizes a pavement distress index and the rate of failures per mile per year; and a deflection criterion, which evaluates the hypothetical contribution of an AC overlay based upon deflection measurements performed on the existing structure. The second part of the study investigated the interface shear strength of tack coats used for bonding AC and portland cement concrete pavement (PCCP), and the rutting resistance of asphalt mixtures for use as overlays on CRCP. A shear test was developed for the tack coats experiment, and it was found that mixes with finer gradations appear to improve the shear strengths of tack coat interfaces. Based on the results of the rutting resistance tests, it is recommended to use Superpave, CMHB, and Type C mixes for AC overlays on CRCP, and to avoid using siliceous river gravel aggregates in these mixes, because of its inferior performance. 17. Key Words Asphalt, concrete, decision tree, reinforced concrete, pavements, thin asphalt concrete overlays, concrete overlays, concrete rehabilitation, AC overlays, shear strength, tack coats 18. Distribution Statement No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161. www.ntis.gov 19. Security Classif. (of report) Unclassified 20. Security Classif. (of this page) Unclassified 21. No. of pages 154 22. Price Form DOT F 1700.7 (8-72) Reproduction of completed page authorized