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CONTINUOUSLY REINFORCED CONCRETE PAVEMENT MANUAL Guidelines for Design, Construction, Maintenance, and Rehabilitation

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CONTINUOUSLY REINFORCED CONCRETE PAVEMENT MANUAL Guidelines for Design, Construction, Maintenance, and Rehabilitation August 2016 CONTINUOUSLY REINFORCED CONCRETE PAVEMENT MANUAL Guidelines for Design, Construction, Maintenance, and Rehabilitation FHWA-HIF-16-026 Authors Jeffery R. Roesler, Ph.D., P.E. University of Illinois at Urbana-Champaign Jacob E. Hiller, Ph.D. Michigan Technological University Alexander S. Brand, Ph.D. University of Illinois at Urbana-Champaign i ACKNOWLEDGEMENTS This manual was produced for the Federal Highway Administration (FHWA) under a cooperative agreement with the Concrete Reinforcing Steel Institute (CRSI). The manual was reviewed and edited for publication by Samuel Tyson, P.E., Federal Highway Administration, and Greg Halsted, P.E., Concrete Reinforcing Steel Institute, with assistance from Shiraz Tayabji, Ph.D., P.E., Advanced Concrete Consultancy LLC. ii iii PREFACE Continuously reinforced concrete pavement (CRCP) was Today, CRCP is designed and constructed as a introduced in the United States almost 100 years ago when pavement of choice for long-life performance, the U.S. Bureau of Public Roads (now the Federal Highway recognizing that initial smoothness will be Administration) constructed a CRCP test section on maintained for decades and that maintenance Columbia Pike in Arlington, Virginia. Since then, CRCP during that time will be minimal. This manual has been constructed in many states in the U.S. and in a provides guidance for materials selection and quality number of other countries. As experience with the design assurance, and for the mechanistic-empirical design, and construction of CRCP has grown, a variety of lessons construction, maintenance, and rehabilitation of learned through practical experience and research have CRCP. Case studies are summarized to document the contributed to the development of best practices for CRCP overall long-life performance of CRCP in the U.S. throughout its life cycle. and in other countries. iv TABLE OF CONTENTS PREFACE.......................................................................................................................iv TABLE OF CONTENTS...................................................................................................v LIST OF FIGURES........................................................................................................vii LIST OF TABLES.............................................................................................................x CHAPTER 1: INTRODUCTION AND OVERVIEW...........................................................1 What is CRCP?....................................................................................................2 When and Why is CRCP Used?..........................................................................3 Overview of Key Points for CRCP.....................................................................4 CRCP Design Overview.....................................................................................5 CRCP Manual Objectives..................................................................................5 Scope of the CRCP Manual...............................................................................5 CHAPTER 2: CRCP DESIGN FUNDAMENTALS.............................................................7 CRCP Behavior...................................................................................................8 CRCP Performance Indicators and Distress Types .......................................10 CHAPTER 3: CRCP STRUCTURAL DESIGN.................................................................15 CRCP Design Methods ....................................................................................16 CRCP Main Design Inputs and Features........................................................20 Best Practices for Selecting CRCP Thickness................................................27 AASHTO Pavement ME Design Input Sensitivity..........................................28 Composite Pavements and CRCP...................................................................31 Life Cycle Cost Analysis and Assessment of CRCP.........................................32 CHAPTER 4: REINFORCEMENT DESIGN AND DETAILS............................................33 Characteristics of Reinforcing Steel..............................................................34 Longitudinal Reinforcement..........................................................................35 Transverse Reinforcement.............................................................................39 CHAPTER 5: CRCP CONSTRUCTION...........................................................................43 Reinforcement Placement.............................................................................44 Paving..............................................................................................................47 Construction Traffic Management.................................................................52 Joints................................................................................................................52 Crossovers.......................................................................................................60 Shoulders, Ramps, and Intersections............................................................62 Construction Techniques for Controlling Crack Spacing.............................66 Inspection........................................................................................................66 v CHAPTER 6: CRCP PERFORMANCE...........................................................................69 CRCP Experience in the U.S............................................................................70 International CRCP Experience......................................................................73 LTPP Program Data.........................................................................................76 CHAPTER 7: CRCP RESTORATION AND RESURFACING...........................................77 Condition Assessment....................................................................................79 Overview of Maintenance and Repair Techniques.......................................81 Overlays on CRCP............................................................................................88 Reconstruction...............................................................................................92 CHAPTER 8: USE OF CRCP AS AN OVERLAY..............................................................95 Unbonded and Bonded CRCP Overlays........................................................96 Structural Design of CRCP Overlays..............................................................97 CHAPTER 9: GUIDE SPECIFICATION FOR CRCP........................................................99 Introduction.................................................................................................100 Guide Specification......................................................................................100 Sources..........................................................................................................105 APPENDIX A: GLOSSARY..........................................................................................107 APPENDIX B: REFERENCES......................................................................................115 vi LIST OF FIGURES Figure 1. The three common concrete pavement types........................................................................................................................2 Figure 2. Newly constructed CRCP (Virginia).....................................................................................................................................3 Figure 3. Reinforcement design and placement is critical for good performance...........................................................................4 Figure 4. Concrete mixture design and materials are critical for good performance......................................................................4 Figure 5. A typical CRCP cross-section.................................................................................................................................................5 Figure 6. Schematic of several factors influencing CRCP behavior...................................................................................................9 Figure 7. A typical CRCP punchout distress.......................................................................................................................................10 Figure 8. Schematic of CRCP punchout mechanism.........................................................................................................................12 Figure 9. Spalling along transverse crack in a CRCP..........................................................................................................................13 Figure 10. Horizontal cracking plane in CRCP...................................................................................................................................14 Figure 11. Structural performance in terms of punchouts as a function of time or traffic loads.................................................17 Figure 12. Functional performance in terms of IRI as a function of time or traffic loads............................................................17 Figure 13. Framework of mechanistic-empirical design procedure for CRCP...............................................................................19 Figure 14. Impact of PCC thickness changes on predicted CRCP punchouts
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