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Cookbook for Rheological Models ‒ Asphalt Binders

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Cookbook for Rheological Models ‒ Asphalt Binders CAIT-UTC-062 Cookbook for Rheological Models – Asphalt Binders FINAL REPORT May 2016 Submitted by: Offei A. Adarkwa Nii Attoh-Okine PhD in Civil Engineering Professor Pamela Cook Unidel Professor University of Delaware Newark, DE 19716 External Project Manager Karl Zipf In cooperation with Rutgers, The State University of New Jersey And State of Delaware Department of Transportation And U.S. Department of Transportation Federal Highway Administration Disclaimer Statement The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Department of Transportation, University Transportation Centers Program, in the interest of information exchange. The U.S. Government assumes no liability for the contents or use thereof. The Center for Advanced Infrastructure and Transportation (CAIT) is a National UTC Consortium led by Rutgers, The State University. Members of the consortium are the University of Delaware, Utah State University, Columbia University, New Jersey Institute of Technology, Princeton University, University of Texas at El Paso, Virginia Polytechnic Institute, and University of South Florida. The Center is funded by the U.S. Department of Transportation. TECHNICAL REPORT STANDARD TITLE PAGE 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. CAIT-UTC-062 4. Title and Subtitle 5. Report Date Cookbook for Rheological Models – Asphalt Binders May 2016 6. Performing Organization Code CAIT/University of Delaware 7. Author(s) 8. Performing Organization Report No. Offei A. Adarkwa Nii Attoh-Okine CAIT-UTC-062 Pamela Cook 9. Performing Organization Name and Address 10. Work Unit No. University of Delaware 11. Contract or Grant No. Newark, DE 19716 DTRT12-G-UTC16 Center for Advanced Infrastructure and Transportation 13. Type of Report and Period Covered Rutgers, The State University of New Jersey Final Report 100 Brett Road 7/1/15 – 12/31/15 Piscataway, NJ 08854 14. Sponsoring Agency Code 12. Sponsoring Agency Name and Address 15. Supplementary Notes U.S. Department of Transportation/OST-R 1200 New Jersey Avenue, SE Washington, DC 20590-0001 16. Abstract Rheology is defined as the science of the deformation and flow of matter (Hackley and Ferraris, 2001). The measurement of rheological properties of matter has become very important in various fields, especially the construction industry, where prevailing external conditions have a great impact on the behavior of construction materials. A vast amount of literature in the past addressed the application of various rheological models of binders (including polymer binders). Several models provide information about the stability, elasticity, thermal susceptibility, chemical composition, and additives of materials. These models are not easy to apply to real world conditions, for example, materials in the presence of heating and cooling. Furthermore, considerable studies using various models to construct better master curves have still proved elusive in providing reasonable simulation fits to the data. This guidebook attempts to provide guidance for the selection (in some cases) of appropriate models in given conditions. 17. Key Words 18. Distribution Statement Asphalt binders; Rheological models; Pavements 19. Security Classification (of this report) 20. Security Classification (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 26 Form DOT F 1700.7 (8-69) Acknowledgments DELDOT Materials Lab – Karl Zipf – Asphalt Engineer Table of Contents 1. DESCRIPTION OF THE PROBLEM ................................................................................... 1 1.1 BACKGROUND ........................................................................................................... 1 1.1.1 MEASURING RHEOLOGICAL PROPERTIES ...................................................... 2 1.1.2 DYNAMIC SHEAR RHEOMETER (DSR) TESTS ................................................. 3 1.1.3 BENDING BEAM RHEOMETER (BBR) TESTS .................................................... 5 1.2 RESEARCH OBJECTIVE ............................................................................................ 6 2. APPROACH ........................................................................................................................ 6 3. FINDINGS ........................................................................................................................... 7 3.1 MECHANICAL ELEMENT MODELS ............................................................................ 7 3.1.1 LINEAR ELASTIC SPRING .................................................................................. 7 3.1.2 LINEAR VISCOUS DASH-POT............................................................................. 8 3.1.3 MAXWELL MODEL............................................................................................... 8 3.1.4 KELVIN MODEL ................................................................................................... 9 3.1.5 HUET MODEL .....................................................................................................10 3.1.6 HUET-SAYEGH MODEL .....................................................................................11 3.1.7 DI BENEDETTO AND NEIFAR (DBN) MODEL ....................................................12 3.1.8 THE 2S2P1D MODEL ..........................................................................................13 3.1.9 THREE-ELEMENT MODELS ...............................................................................13 3.1.10 GENERALIZED MODELS ....................................................................................15 3.2 EMPIRICAL ALGEBRAIC EQUATION MODELS ........................................................16 3.2.1 JONGEPIER AND KUILMAN’S MODEL ..............................................................16 3.2.2 CHRISTENSEN AND ANDERSON (CA) MODEL ................................................17 3.2.3 CHRISTENSEN ANDERSON AND MARASTEANU (CAM) MODEL ...................18 3.2.4 POLYNOMIAL MODEL ........................................................................................18 3.2.5 SIGMOIDAL MODEL ...........................................................................................19 4. CONCLUDING REMARKS ................................................................................................19 List of Figures Figure 1. Phase Angle for Elastic solids, Viscous liquids, and Viscoelastic Materials ................. 4 Figure 2. Elastic Body ................................................................................................................ 7 Figure 3. Linear Viscous Dash-pot ............................................................................................. 8 Figure 4. Maxwell Model ............................................................................................................ 9 Figure 5. Kelvin Model ............................................................................................................... 9 Figure 6. Huet Model.................................................................................................................10 Figure 7. Huet-Sayegh Model ...................................................................................................11 Figure 8. Di Benedetto and Neifar (DBN) Model ........................................................................12 Figure 9. The 2S2P1D Model ....................................................................................................13 Figure 10. Three-Element Model ...............................................................................................14 Figure 11. Generalized Maxwell Model .....................................................................................15 Figure 12. Generalized Kelvin Chain .........................................................................................16 Figure 13. Definition of Parameters from the Christensen and Anderson Model ........................18 List of Tables Table 1. Classification of Creep ................................................................................................. 5 Table 2. Classification of Relaxation .......................................................................................... 6 1. DESCRIPTION OF THE PROBLEM Rheology has been a powerful tool for characterizing and quantifying asphalt binder properties. Furthermore, it has been established that the properties of the asphalt binder have a major influence on pavement performance and on the rate of deterioration under different load and environmental conditions. Rheological testing and models of asphalt binder are widely used to describe and evaluate the behavior of binder. The majority of these rheological models are based on time derivatives of integer order. The cookbook attempts to present the assumptions and models applied to asphalt binder for pavement design. The models are examined presented in the particular conditions under which experiments are carried out on the binders, particularly in shear flow and, for a solid as opposed to liquid state, a bending beam rheometer). 1.1 BACKGROUND Rheology is defined as the study of the flow and deformation of material. In flow, elements of the liquids are deforming, and adjacent points in the liquids are moving relative to one another. The two basic flows are: a) Shear flow – when liquid elements flow over or past each other
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