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Fiber in Continuously Reinforced Concrete Pavements 6 Technical Report Documentation Page 1. Report No. 2. Government 3. Recipient’s Catalog No. FHWA/TX-07/0-4392-2 Accession No. 4. Title and Subtitle 5. Report Date January 2006; Revised December 2006 Fiber in Continuously Reinforced Concrete Pavements 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Dr. Kevin Folliard, David Sutfin, Ryan Turner, and David P. 0-4392-2 Whitney 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Center for Transportation Research 11. Contract or Grant No. The University of Texas at Austin 0-4392 3208 Red River, Suite 200 Austin, TX 78705-2650 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered Texas Department of Transportation Technical Report 9/1/01–8/31/03 Research and Technology Implementation Office 14. Sponsoring Agency Code P.O. Box 5080 Austin, TX 78763-5080 15. Supplementary Notes Project conducted in cooperation with the Federal Highway Administration and the Texas Department of Transportation. Project Title: Use of Fibers in Concrete Pavement 16. Abstract Continuously reinforced concrete pavement (CRCP) is a major form of highway pavement in Texas due to its increase in ride quality, minimal maintenance, and extended service life. However, CRCP may sometimes experience pavement distress that results in early failure, either due to under-design or the use of poor construction materials. Significant effort has been made to improve the performance of some of these materials (e.g. siliceous river gravel) to achieve an acceptable level of performance but has been unable to provide a practical solution. This research study investigates whether fiber reinforcement may solve some of the problems associated with siliceous river gravel, particularly spalling. The main objectives of this study were to: (1) Conduct a comprehensive literature review in order to determine the current state of the art regarding CRCP design and behavior as well as the role that fiber reinforcement may have in improving its performance; (2) Perform field investigations in order to verify constructability and workability of fibers in CRCP construction; (3) Perform frequent monitoring to evaluate the effect of fibers on crack spacing, crack width, and spalling development; (4) Perform laboratory testing that validate the effect of fibers on typical concrete paving mixes; (5) Provide TxDOT with recommendations as to possible changes in the construction and design specifications of CRCP, which could serve to reduce or prevent spalling. Because the manifestation of spalling in CRCP may sometimes take several years, it is difficult to draw firm conclusions from this two-year study. However, based on the findings within the time frame of this project, fiber reinforcement did appear to prevent or limit spalling in the field test sections, when compared to the control sections that did not contain fibers. It is recommended that future monitoring of these test sections be performed to fully characterize the long-term efficacy of fibers in reducing or preventing spalling of CRCP. 17. Key Words 18. Distribution Statement CRCP, continuously reinforced concrete No restrictions. This document is available to the pavements, pavements public through the National Technical Information Service, Springfield, VA 22161; www.ntis.gov 19. Security Classif. (of report) 20. Security Classif. (of this page) 21. No. of pages 22. Price Unclassified Unclassified 198 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized Fiber in CRCP Pavements Dr. Kevin Folliard David Sutfin Ryan Turner David P. Whitney CTR Technical Report: 0-4392-2 Report Date: January 2006; Revised December 2006 Research Project: 0-4392 Research Project Title: Use of Fibers in Concrete Pavement Sponsoring Agency: Texas Department of Transportation Performing Agency: Center for Transportation Research at The University of Texas at Austin Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. Center for Transportation Research The University of Texas at Austin 3208 Red River Austin, TX 78705 www.utexas.edu/research/ctr Copyright © 2007 Center for Transportation Research The University of Texas at Austin All rights reserved Printed in the United States of America iv Disclaimers Authors’ Disclaimer: The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official view or policies of the Federal Highway Administration or the Texas Department of Transportation. This report does not constitute a standard, specification, or regulation. Patent Disclaimer: There was no invention or discovery conceived or first actually reduced to practice in the course of or under this contract, including any art, method, process, machine manufacture, design or composition of matter, or any new useful improvement thereof, or any variety of plant, which is or may be patentable under the patent laws of the United States of America or any foreign country. Engineering Disclaimer NOT INTENDED FOR CONSTRUCTION, BIDDING, OR PERMIT PURPOSES. Project Engineer: Dr. David W. Fowler Professional Engineer License Number: Texas No 27859 P. E. Designation: Researcher v Acknowledgments The authors would like to thank Charles Gaskin and James Kosel of TxDOT. Products Product 3 (P3) is included in this report as Chapter 6, Summary, Conclusions and Recommendations vi Table of Contents Chapter 1. Introduction................................................................................................................ 1 1.1 Research Background ............................................................................................................1 1.2 Research Objectives...............................................................................................................1 1.3 Scope of Report .....................................................................................................................1 Chapter 2. Literature Review ...................................................................................................... 3 2.1 Continuously Reinforced Concrete Pavement.......................................................................4 2.2 Materials and Mixture Proportions........................................................................................4 2.2.1 Cement Type.................................................................................................................. 5 2.2.2 Water-to-Cementitious Ratio ......................................................................................... 5 2.2.3 Aggregate Type.............................................................................................................. 5 2.2.4 Chemical Admixtures .................................................................................................... 5 2.2.5 Supplementary Cementing Materials............................................................................. 6 2.2.6 Reinforcing Steel ........................................................................................................... 6 2.2.7 Sub-base Material .......................................................................................................... 7 2.3 Other Design Concepts and Issues.........................................................................................8 2.3.1 Allowable Crack Width ................................................................................................. 8 2.3.2 Slab Thickness ............................................................................................................... 9 2.3.3 Aggregate Type.............................................................................................................. 9 2.3.4 Sub-base....................................................................................................................... 10 2.3.5 Subgrade ...................................................................................................................... 10 2.4 Performance Issues ..............................................................................................................10 2.4.1 Spalling ........................................................................................................................ 10 2.4.2 Punchouts..................................................................................................................... 12 2.4.3 Widened Transverse Cracks......................................................................................... 13 2.4.4 Longitudinal Cracks..................................................................................................... 14 2.4.5 Crack Width ................................................................................................................. 15 2.4.6 Crack Spacing .............................................................................................................. 15 2.4.7 Coefficient of Thermal Expansion............................................................................... 16 2.5 Construction and Paving......................................................................................................16 2.5.1 Paving Equipment........................................................................................................ 16 2.5.2 Roller Screeding..........................................................................................................
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