Asset management

Cover of Review of the Traffic Speed Deflectograph: Final Project Report
Review of the Traffic Speed Deflectograph: Final Project Report
  • Publication no: AP-R395-12
  • ISBN: 978-1-921991-09-7
  • Published: 27 January 2012

This project was established to enable ARRB and Austroads member authorities to work with the RTA to develop an independent national perspective on the applicability of the TSD to Australian conditions and practices. As the TSD is a newly developed device there is little publicly available information relating to its performance, and some of its fundamentals of operation. The project team collaborated with TSD operators, the UK Transport Research Laboratory (TRL) and the DRD, to facilitate knowledge exchange and address gaps in the literature.

The purpose of this report is to assist practitioners in understanding the TSD and its operational parameters, consolidate recent international TSD investigations and findings, present the findings of the research and analysis of TSD data that was carried out, and inform Austroads members regarding the applicability of the TSD in Australia.

  • 1. INTRODUCTION
    • 1.1. Background
    • 1.2. Structure of this Report
    • 1.3. Potential use in Australian Asset Management Practice
    • 1.4. Pavement Strength
  • 2. AUSTRALIAN CONDITIONS
    • 2.1. General
    • 2.2. Climate
    • 2.3. Pavement Composition and Surfacing
      • 2.3.1. Pavement Strength Rating
    • 2.4. Distances and Speed
  • 3. THE TRAFFIC SPEED DEFLECTOMETER (TSD)
    • 3.1. Description of the TSD
    • 3.2. Configuration in Australia
      • 3.2.1. Load Level
      • 3.2.2. Prime Mover
      • 3.2.3. Sensor Location
      • 3.2.4. Laser Angle
      • 3.2.5. Speed
      • 3.2.6. Temperature Control
    • 3.3. Data Interpretation
      • 3.3.1. General
      • 3.3.2. Surface Curvature Index (SCI)
      • 3.3.3. Slope
      • 3.3.4. Maximum Deflection (D0)
      • 3.3.5. Data Rate
  • 4. PREVIOUS TESTING AND EVALUATION
    • 4.1. General
    • 4.2. Validation of the Location Referencing System and Distance Measurement
    • 4.3. General Repeatability Testing
    • 4.4. Factors Affecting Repeatability
      • 4.4.1. Ambient and Road Surface Temperature
      • 4.4.2. Vehicle Testing Speed
      • 4.4.3. Effect of Axle Load
      • 4.4.4. Pavement Differentiation (Strong vs. Weak)
      • 4.4.5. Road Surface Characteristics
    • 4.5. Calibration
      • 4.5.1. Geometric Calibration
      • 4.5.2. Absolute Calibration
    • 4.6. UKTSD Development
  • 5. RTA PRACTITIONERS TSD EXPERIENCE
    • 5.1. General
    • 5.2. Background
    • 5.3. DTSD Mobilisation and Shipment
    • 5.4. Shakedown Trial Sites
    • 5.5. Timing and Network Coverage
    • 5.6. Data Collection
    • 5.7. Use of Data
    • 5.8. Operational Experiences
    • 5.9. Summary
  • 6. ANALYSIS AND INTERPRETATION OF TRIAL DATA
    • 6.1. Trial Sites and Testing Programs
      • 6.1.1. Trial Site Data
      • 6.1.2. Strength Characteristics
      • 6.1.3. Homogenous Sections
    • 6.2. Repeatability
      • 6.2.1. Short-term Repeatability
      • 6.2.2. Long-term Repeatability
    • 6.3. Correlation with other Deflection Devices
    • 6.4. Differentiation between Weak and Strong Pavements
    • 6.5. Recording and Reporting Intervals
      • 6.5.1. Information Quality Level (IQL)
      • 6.5.2. Raw and Machine Data
      • 6.5.3. Simple Aggregation Method
      • 6.5.4. One Metre Reporting Length
      • 6.5.5. Five to 20 m Reporting Length
      • 6.5.6. Fifty to 100 m Reporting Length
    • 6.6. Influence of Surface Characteristics
      • 6.6.1. Surface Type
      • 6.6.2. Longitudinal Profile/Roughness
      • 6.6.3. Dynamic Load
    • 6.7. Influence of Pavement Characteristics
    • 6.8. Temperature
    • 6.9. Operational Parameters
      • 6.9.1. Survey Speed
    • 6.10. Data Rate
    • 6.11. Australian TSD Indicators
      • 6.11.1. Indicators
      • 6.11.2. Percentage Distribution Bins
    • 6.12. Analysis Summary
  • 7. IMPLICATIONS FOR REHABILITATION DESIGN
    • 7.1. Use of Deflection Data in Rehabilitation Design
    • 7.2. Screening
    • 7.3. Structural Evaluation and Overlay Design
      • 7.3.1. Granular Overlays on Existing Granular Pavements with Thin Bituminous Surfacing (Chartbased)
      • 7.3.2. Asphalt Overlays on Flexible Pavements without Cemented Materials (Chartbased)
      • 7.3.3. Asphalt or Granular Overlays on all Flexible Pavements (General Mechanistic Procedure)
      • 7.3.4. Asphalt Overlays on Rigid Pavements
      • 7.3.5. Concrete Overlays on Flexible Pavements
      • 7.3.6. Concrete Overlays on Rigid Pavements
      • 7.3.7. Summary
  • 8. CONSIDERATIONS FOR AUSTRALIAN USE
    • 8.1. Benefits
    • 8.2. Key Concerns
    • 8.3. Australian Configuration Considerations
    • 8.4. Member Needs
  • 9. CONCLUSIONS
    • 9.1. Research Goals
      • 9.1.1. Research Goals 1 and 2
      • 9.1.2. Research Goal 3
      • 9.1.3. Research Goal 4
      • 9.1.4. Research Goal 5
      • 9.1.5. Research Goal 6
    • 9.2. General Conclusions
  • REFERENCES