Pavement

Cover of Guide to Pavement Technology Part 5: Pavement Evaluation and Treatment Design
Guide to Pavement Technology Part 5: Pavement Evaluation and Treatment Design
  • Publication no: AGPT05-19
  • ISBN: 978-1-925854-67-1
  • Published: 20 November 2019
  • Edition: 4.1

Guide to Pavement Technology Part 5: Pavement Evaluation and Treatment Design provides advice for the investigation of existing sealed road pavements and the selection and design of pavement strategies/treatments. It covers pavement investigation, testing and evaluation, identification of causes and modes of distress, and treatment options.

Knowledge of pavement technology is of critical importance for all transport agencies in Australia and New Zealand. Austroads and others (e.g. state road agencies, local government and industry) have amassed a great deal of knowledge on pavement technologies, techniques and considerations. The purpose of the Austroads Guide to Pavement Technology is to assemble this knowledge into a single authoritative guide that will be a readily available, accessible and comprehensive resource for practitioners in Australia and New Zealand.

The target audience for the Austroads Guide to Pavement Technology includes all those involved with the management of roads, including industry and students seeking to learn more about the fundamental concepts, principles, issues and procedures associated with pavement technology.

The advice has been generally developed from the approaches followed by Austroads’ member authorities. However, as it encompasses the wide range of materials and conditions found in Australia and New Zealand, some parts are broadly based. Treatment selection is related to availability of materials and knowledge of their performance in any particular locality.

Edition 4.1, published November 2019, corrects the removed and replaced existing unbound granular material value in Table L.1.

In Edition 4.0 published in July 2019:

  • Editorial changes and technical updates have been made throughout
  • Changes have been made to the mechanistic-empirical design of strengthening treatments for flexible pavements
  • A new design process for calculating granular overlays using Traffic Speed Deflectometer deflections has been added
  • Asphalt overlay design charts have been deleted.
  • 1. Introduction
    • 1.1 Overview of the Rehabilitation Design Process
  • 2. Project Definition
    • 2.1 Project Scope
    • 2.2 Background Data
    • 2.3 Investigation and Design Proposal
    • 2.4 Design Report Content and Structure
    • 2.5 Acceptable Risk and Project Reliability
  • 3. Pavement Data and Inspection
    • 3.1 General
    • 3.2 Historical Data
      • 3.2.1 Original Pavement Design
      • 3.2.2 Construction Details
      • 3.2.3 Maintenance and Rehabilitation Records
      • 3.2.4 Climatic Conditions
      • 3.2.5 Effect of Traffic on Past Performance
    • 3.3 Field Survey
      • 3.3.1 Introduction
      • 3.3.2 Visual Condition Data
      • 3.3.3 Other Site and Environment Information
  • 4. Investigative Testing on the Pavement Surface
    • 4.1 Introduction
    • 4.2 Types of Forensic Testing
    • 4.3 Roughness
    • 4.4 Rutting
    • 4.5 Cracking
    • 4.6 Skid Resistance
    • 4.7 Surface Texture
    • 4.8 Use of Ground Penetrating Radar
    • 4.9 Surface Deflection of Flexible Pavements
      • 4.9.1 General
      • 4.9.2 Methods of Testing
      • 4.9.3 Selection of Test Sites
      • 4.9.4 Response to Load
      • 4.9.5 Measurement of Pavement Temperature
    • 4.10 Surface Deflection of Rigid Pavements
      • 4.10.1 Surface Deflection Data
  • 5. Pavement Composition and Subgrade Characterisation
    • 5.1 Introduction
    • 5.2 Coring of Bound Materials
    • 5.3 Pavement Pits and Trenches
    • 5.4 In situ CBR from DCP Testing
  • 6. Causes and Modes of Distress
    • 6.1 Introduction
    • 6.2 Classification of the Causes of Distress
    • 6.3 Distress Modes
    • 6.4 Evaluation of Pavement Condition Data
      • 6.4.1 Visual Condition
      • 6.4.2 Roughness
      • 6.4.3 Rutting and Shape Loss
      • 6.4.4 Skid Resistance
      • 6.4.5 Surface Texture
    • 6.5 Surface Deflections
      • 6.5.1 Flexible Pavements
      • 6.5.2 Rigid Pavements
    • 6.6 Pavement Composition and Material Quality
      • 6.6.1 Flexible Pavements
      • 6.6.2 Rigid Pavements
    • 6.7 Subgrade Classification and Strength
    • 6.8 Structural Adequacy of Original Design
  • 7. Selection of Treatments for Flexible Pavements
    • 7.1 Introduction
    • 7.2 Overview of Treatments Options
    • 7.3 Treatments to Improve Drainage
      • 7.3.1 General
      • 7.3.2 Surface Drainage System
      • 7.3.3 Subsurface Drainage System
      • 7.3.4 Filter Layers
      • 7.3.5 Types of Pavement Drains
      • 7.3.6 Design and Construction Issues
    • 7.4 Treatments for Surfacing Distress
      • 7.4.1 Introduction
      • 7.4.2 Sprayed Seals
      • 7.4.3 Holding Actions
      • 7.4.4 Asphalt Work
      • 7.4.5 Recycling of Asphalt
    • 7.5 Treatments for Strengthening Pavements
      • 7.5.1 Introduction
      • 7.5.2 Heavy Patching
      • 7.5.3 Asphalt Overlay
      • 7.5.4 Granular Overlay
      • 7.5.5 Concrete Overlay
      • 7.5.6 In situ Stabilisation of Granular Pavements General
      • 7.5.7 Granular (Mechanical) Stabilisation
      • 7.5.8 Cement and Cementitious Stabilisation
      • 7.5.9 Lime Stabilisation
      • 7.5.10 Bitumen Stabilisation
      • 7.5.11 Other Chemical Stabilising Binders
    • 7.6 Treatments for Pavements on Expansive Subgrades
    • 7.7 Design and Construction Considerations
      • 7.7.1 Community Attitudes
      • 7.7.2 Grade Line Restrictions
      • 7.7.3 Depth Restrictions Due to Services
      • 7.7.4 Road Geometry
      • 7.7.5 New Pavement Abutting an Existing Pavement
      • 7.7.6 Pavement Jointing Considerations
      • 7.7.7 Shoulder Sealing
      • 7.7.8 Staged Construction
      • 7.7.9 Construction Under Traffic
      • 7.7.10 Risk, Design Sensitivity, Construction Tolerances and Degree of Control
      • 7.7.11 Availability of Plant, Personnel and Material
  • 8. Treatments for Rigid Pavements
    • 8.1 Introduction
    • 8.2 Overview of Treatments Options
    • 8.3 Treatments to Improve Drainage
    • 8.4 Treatments for Surfacing Distress
      • 8.4.1 General
      • 8.4.2 Bonded Concrete Topping
      • 8.4.3 Grinding/profiling
    • 8.5 Treatments for Joint Distress
      • 8.5.1 General
      • 8.5.2 Joint Seal Replacement
      • 8.5.3 Joint Spall Repairs
    • 8.6 Treatments for Structural Distress
      • 8.6.1 General
      • 8.6.2 Slab Undersealing
      • 8.6.3 Slab Cross-stitching
      • 8.6.4 Full-depth Concrete Patching
      • 8.6.5 Asphalt Overlays
      • 8.6.6 Concrete Overlays
      • 8.6.7 Slab Fracturing Techniques with Overlay
    • 8.7 Treatments for Pavements on Expansive Subgrades
    • 8.8 Design and Construction Considerations
  • 9. Empirical Design of Granular Overlays for Flexible Pavements
    • 9.1 Introduction
    • 9.2 Characteristic Deflections
      • 9.2.1 General
      • 9.2.2 Adjustment of Deflections to Account for Seasonal Moisture Variations
      • 9.2.3 Standardisation of Deflections
      • 9.2.4 Adjustment of Maximum Deflections to Account for the Testing Temperature
      • 9.2.5 Selection of Homogeneous Sections
      • 9.2.6 Calculation of Characteristic Deflections
    • 9.3 Design Periods and Traffic Loading
    • 9.4 Design Deflections
    • 9.5 Determination of Granular Overlay Thickness
  • 10. Mechanistic-empirical Procedure of Designing Strengthening Treatments for Flexible Pavements
    • 10.1 Introduction
    • 10.2 Mechanistic-empirical Procedure
    • 10.3 Design Periods and Traffic Loadings
    • 10.4 Selection of Homogeneous Sub-sections
    • 10.5 Back-calculation of Moduli from Measured Deflections
      • 10.5.1 Introduction
      • 10.5.2 Selection of Deflection Bowls for Modulus Back-calculation
      • 10.5.3 Pavement and Subgrade Configuration
    • 10.6 Selection of Trial Treatment
      • 10.6.1 General
      • 10.6.2 Cementitious Stabilisation of Pavement Layers
      • 10.6.3 Foamed Bitumen Stabilisation of Pavement Layers
    • 10.7 Procedures for Elastic Characterisation
      • 10.7.1 Introduction
      • 10.7.2 Subgrade
      • 10.7.3 Selected Subgrade and Lime-stabilised Subgrade
      • 10.7.4 Unbound and Modified Granular Materials
      • 10.7.5 Asphalt
      • 10.7.6 Cemented Material and Lean-mix Concrete
      • 10.7.7 Foamed Bitumen Stabilised Material
    • 10.8 Procedures for Determining Critical Strains
    • 10.9 Performance Relationships
    • 10.10 Treatment Design
      • 10.10.1 Introduction
      • 10.10.2 Design Method
  • 11. Concrete Overlays on Flexible Pavements
  • 12. Thickness Design of Structural Treatments for Rigid Pavements
    • 12.1 Introduction
    • 12.2 Asphalt Overlays on Rigid Pavements
    • 12.3 Concrete Overlays on Rigid Pavements
  • 13. Economic Comparison of Alternative Treatments
    • 13.1 Introduction
    • 13.2 Method for Economic Comparison
    • 13.3 Economic Parameters
      • 13.3.1 Initial Rehabilitation Costs
      • 13.3.2 Subsequent Maintenance/Rehabilitation Costs
      • 13.3.3 Salvage Value
      • 13.3.4 Real Discount Rate
      • 13.3.5 Analysis Period
    • 13.4 Road User Costs
    • 13.5 Predicting Performance of Treatments
    • 13.6 Example of Whole-of-Life Costing of Alternatives
  • References
  • Appendix A Identification, Causes and Treatment of Visual Distress
  • Appendix B Weighted Mean Annual Pavement Temperatures
  • Appendix C Adjustment of Deflections for Temperature
  • Appendix D Identifying Homogeneous Sub-sections Using the Cumulative Difference Approach
  • Appendix E Granular Overlay Thickness Design Worksheets
  • Appendix F Example of the Empirical Design of a Granular Overlay on a Flexible Pavement
  • Appendix G Composite Modulus Calculation
  • Appendix H Elastic Characterisation of Foamed Bitumen Stabilised Materials
  • Appendix I Calculation of Past Traffic Loading
  • Appendix J Asphalt Inlay Design Example
  • Appendix K Cement-stabilised Base Design Example
  • Appendix L Example of Granular Overlay Thickness Design Considering Lime Stabilisation of Subgrade
  • Appendix M Modified Granular Base Design Example
  • Appendix N Foamed Bitumen Stabilisation Design Example
  • Appendix O Example of the Design of Concrete Overlays on Flexible Pavements
  • Appendix P Example of the Design of Asphalt Overlays on Rigid Pavements
  • Appendix Q Example of Economic Evaluation of Alternatives