IMPLEMENTING THE MECHANISTIC-EMPIRICAL

PAVEMENT DESIGN GUIDE: TECHNICAL REPORT

Sponsored by

the Iowa Highway Research Board

(IHRB Project TR-509)

and

the Iowa Department of Transportation

(CTRE Project 03-166)

Department of Civil, Construction and Environmental Engineering

May 2005

Disclaimer Notice

The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the Iowa Department of Transportation or the Iowa Highway Research Board. The sponsor(s) assume no liability for the contents or use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The sponsor(s) do not endorse products or manufacturers.

About CTRE/ISU

The mission of the Center for Transportation Research and Education (CTRE) at Iowa State Uni-versity is to develop and implement innovative methods, materials, and technologies for improv-ing transportation efficiency, safety, and reliability while improving the learning environment of students, faculty, and staff in transportation-related fields.

Technical Report Documentation Page

1. Report No. IHRB Project TR-509

2. Government Accession No. 3. Recipients Catalog No.

4. Title and Subtitle Implementing the Mechanistic-Empirical Pavement Design Guide: Technical Report

5. Report Date May 2005 6. Performing Organization Code

7. Author(s) Brian Coree, Halil Ceylan, and Dale Harrington

8. Performing Organization Report No. CTRE Project 03-166

9. Performing Organization Name and Address Center for Transportation Research and Education Iowa State University 2901 South Loop Drive, Suite 3100 Ames, IA 50010-8634

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

12. Sponsoring Organization Name and Address Iowa Highway Research Board Iowa Department of Transportation 800 Lincoln Way Ames, IA 50010

13. Type of Report and Period Covered Technical Report 14. Sponsoring Agency Code

15. Supplementary Notes Visit www.ctre.iastate.edu for color PDF files of this and other research reports. 16. Abstract

With the release of the new Mechanistic-Empirical Pavement Design Guide (MEPDG), pavement design has taken a quantum leap forward. The current 1993 design guide is solidly based on the empirical interpretation of the results of the 1960 American Association of State Highway and Transportation Officials (AASHTO) Road Test.

This report seeks to outline the technical aspects of the new MEPDG. Full detail is essentially impossible and impractical, since the release of the MEPDG was accompanied by eighteen volumes of technical justification and background. Consequently, this report seeks only to provide a potential user with a practical understanding of the workings of the new guide, with only sufficient technical depth to aid in understanding.

17. Key Words design guideimplementationinput parameterspavement designpavement performance

18. Distribution Statement No restrictions.

19. Security Classification (of this report) Unclassified.

20. Security Classification (of this page) Unclassified.

21. No. of Pages

94 plus appendices

22. Price

NA

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized

IMPLEMENTING THE MECHANISTIC-EMPIRICAL

PAVEMENT DESIGN GUIDE: TECHNICAL

REPORT

May 2005

Sponsored by the Iowa Highway Research Board (IHRB Project TR-509)

Principal Investigator Brian Coree

Assistant Professor, Department of Civil, Construction and Environmental Engineering

Iowa State University

Co-Principal Investigators Halil Ceylan

Assistant Professor, Department of Civil, Construction and Environmental Engineering

Iowa State University

Dale Harrington

Associate Director for Pavements, Center for Transportation Research and Education

Iowa State University

Research Assistants Alper Guclu, Sunghwan Kim, and Kasthurirangan Gopalakrishnan

Preparation of this report was financed in part

through funds provided by the Iowa Department of Transportation

through its research management agreement with

the Center for Transportation Research and Education,

CTRE Project 03-166

Center for Transportation Research and Education

Iowa State University

2901 Loop Drive, Suite 3100

Ames, IA 50010-8632

Phone: 515-294-8103

Fax: 515-294-0467

www.ctre.iastate.edu

TABLE OF CONTENTS

1 INTRODUCTION .............................................................................................................. 1

1.1 Overview....................................................................................................................... 1

1.2 What is the Mechanistic-Empirical Pavement Design Guide? ..................................... 1

1.3 Comments ..................................................................................................................... 2

1.4 Summary ....................................................................................................................... 3

2 HOW DOES IT WORK?.................................................................................................... 4

2.1 Overview of Process ..................................................................................................... 4

2.2 Environment.................................................................................................................. 5

2.3 Traffic ........................................................................................................................... 6

2.4 Materials ....................................................................................................................... 7

2.4.1 Structural.............................................................................................................. 7

2.4.2 Non-Structural...................................................................................................... 8

2.5 Structural Analysis........................................................................................................ 8

2.5.1 Rigid (PCC) Pavement......................................................................................... 8

2.5.2 Flexible (HMA) Pavement................................................................................... 8

2.6 Incremental Distress...................................................................................................... 9

2.7 Levels of Input .............................................................................................................. 9

2.8 Output ......................................................................................................................... 10

3 COMPONENT INPUT MODULES................................................................................. 11

3.1 General Information.................................................................................................... 12

3.1.1 Initial screen....................................................................................................... 12

3.1.2 Site/Project Identification .................................................................................. 13

3.1.3 Performance Criteria Input ................................................................................ 14

3.2 Traffic Module ............................................................................................................ 15

3.3 Environmental (Climate) Module ............................................................................... 21

3.4 Structure (Materials) ................................................................................................... 23

3.4.1 Design Features (PCC only) .............................................................................. 23

3.4.2 Drainage and Surface Properties........................................................................ 24

3.4.3 Layers................................................................................................................. 25

3.4.3.1 Materials ..................................................................................................... 27

3.4.3.1.1 Concrete ................................................................................................ 27

3.4.3.1.2 Asphalt Materials .................................................................................. 30

3.4.3.1.3 Asphalt Thermal Cracking.................................................................... 33

3.4.3.1.4 Stabilized Materials .............................................................................. 35

3.4.3.1.5 Unbound (Granular) Materials.............................................................. 35

3.4.3.1.6 Subgrade Materials ............................................................................... 39

4 ANALYTIC COMPUTATION........................................................................................ 39

4.1 Time-stepping ............................................................................................................. 39

4.2 Material Moduli .......................................................................................................... 40

5 INCREMENTAL DISTRESS .......................................................................................... 41

5.1 Transfer Functions ..............