Road safety

Cover of Investigation of Key Crash Types: Rear-end Crashes in Urban and Rural Environments
Investigation of Key Crash Types: Rear-end Crashes in Urban and Rural Environments
  • Publication no: AP-R480-15
  • ISBN: 978-1-925294-11-8
  • Published: 16 March 2015

This report collates research into factors contributing to the incidence and severity of rear-end crashes in urban and rural environments in Australia and New Zealand. It also identifies a number of possible pertinent mitigation measures.

A crash data analysis (for a five year period 2006-2010) and inspection of key crash sites were conducted to supplement available research on this topic. Recommendations are made on practical ways to reduce the incidence and severity of rear-end crashes within the working environment of the Safe System approach.

The National Road Safety Strategy has identified intersection crashes as one of the most frequent crash types occurring on Australian roads. As rear-end crashes are a common collision type at intersections, they have been targeted as part of the strategy.

  • Summary
  • Contents
  • 1. Introduction
    • 1.1. Background
    • 1.2. Objective
    • 1.3. Method
    • 1.4. Terms Used in the Report
      • 1.4.1. Rear-end Crash
      • 1.4.2. Vehicle Involvement
      • 1.4.3. Turn Manoeuvre
  • Task 1 – Literature review and internet search
  • Task 2 – Collection and analysis of crash data
  • Task 3 – Site investigations
  • 2. Literature Review
    • 2.1. Overview of the Rear-end Crash Issue
      • 2.1.1. General Prevalence and Significance of Rear-end Crashes
      • 2.1.2. Prevalence in Urban vs Rural Areas
      • 2.1.3. Lead Vehicle Movements
      • 2.1.4. Rear-end Crash Injuries
    • 2.2. Road Environment Crash Contributory Factors
      • 2.2.1. Intersections
      • 2.2.2. Factors Relevant to Signalised Intersections
      • 2.2.3. Vehicle Headway
      • 2.2.4. Traffic Conditions
      • 2.2.5. Work Zones
      • 2.2.6. Road Geometry
      • 2.2.7. Visibility
      • 2.2.8. Road Surface
      • 2.2.9. Parked Vehicles
    • 2.3. Driver-based Crash Contributory Factors
      • 2.3.1. Driver Inattention
      • 2.3.2. Medical Conditions
      • 2.3.3. Influence of Alcohol
      • 2.3.4. Age
      • 2.3.5. Gender
      • 2.3.6. Restraint Usage
    • 2.4. Vehicle-based Crash Contributory Factors
      • 2.4.1. Vehicle Type
      • 2.4.2. Struck vs Striking Vehicles
      • 2.4.3. Vehicle Seat and Head Restraint Combination
    • 2.5. Road Engineering Countermeasures
      • 2.5.1. General Intersection Treatments
      • 2.5.2. Turning Treatments
      • 2.5.3. Signalised Intersection Treatments
      • 2.5.4. Measures to Address Increased Risk at Work Zones
      • 2.5.5. Speed Management
      • 2.5.6. Treatments for Tailgating
      • 2.5.7. Treatments for Congestion
      • 2.5.8. Improved Skid Resistance
      • 2.5.9. Improved Driveway Delineation
    • 2.6. Vehicle-based Countermeasures
      • 2.6.1. Forward Collision Avoidance and Warning Systems
      • 2.6.2. Adaptive Cruise Control
      • 2.6.3. Following Distance Warning
      • 2.6.4. Rearward Headway Monitoring
      • 2.6.5. Brake Assist
      • 2.6.6. Enhanced Rear Signal Systems
      • 2.6.7. Improved Rear Visibility
      • 2.6.8. Head-restraint/Seat Combination-based Mitigation
  • 3. Crash Data Analysis
    • 3.1. Overview
      • 3.1.1. Average Annual Rear-end Casualty Crashes by Jurisdictions
      • 3.1.2. Rear-end Crash Severity by Road Environment
      • 3.1.3. Rear-end Crash Trends over Study Period
      • 3.1.4. Breakdown of Rear-end Casualty Crash Types
    • 3.2. Timing and Environmental factors
      • 3.2.1. Day-of-week
      • 3.2.2. Time-of-day
      • 3.2.3. Lighting Conditions
      • 3.2.4. ‘Rain Condition’
      • 3.2.5. Speed Zone
      • 3.2.6. Road Alignment
      • 3.2.7. Road Surface in Rural Environments
      • 3.2.8. Crash Location Type
      • 3.2.9. Temporary Change to Environment
    • 3.3. Crash Factors
      • 3.3.1. Number of Vehicles Involved
      • 3.3.2. Lead Vehicle Movement
      • 3.3.3. Driver Involvement
    • 3.4. Vehicle Factors
      • 3.4.1. Vehicle Age
      • 3.4.2. Vehicle Types Involved
    • 3.5. Driver Factors
      • 3.5.1. Driver Age
      • 3.5.2. Driver BAC
      • 3.5.3. Driver Gender
    • 3.6. Key Findings of the Crash Analysis
  • Considerations during data analysis
  • Disaggregation based on road environment
  • Disaggregation based on crash severity
  • Considerations when interpreting crash data
  • Crash codes used to define rear-end crashes
  • 4. Site Investigations
    • 4.1. Findings
      • 4.1.1. Road Environment
      • 4.1.2. Road Design
      • 4.1.3. Disruptions to Traffic Flow
      • 4.1.4. Intersection Configuration
      • 4.1.5. Signalised Intersection Design
      • 4.1.6. Automated Enforcement
      • 4.1.7. Pedestrian Provision
    • 4.2. Key Findings of the Site Inspections
  • 5. Key Findings and Discussion
    • 5.1. Rear-end Crash Contributory Factors
      • 5.1.1. Humans
      • 5.1.2. Vehicles
      • 5.1.3. Road Environment
    • 5.2. Factors Affecting Crash Severity
  • 6. Conclusions and Recommendations
    • 6.1. Conclusions
      • 6.1.1. Recommended Actions to Reduce the Incidence of Rear-end Crashes
    • 6.2. Issues for Consideration as Part of the Austroads Guides Updates
    • 6.3. Further Austroads Work
  • Guide to Traffic Management Part 6: Intersections, Interchanges and Crossings (Austroads 2013b)
  • Guide to Traffic Management Part 8: Local Area Traffic Management (Austroads 2008b – under review)
  • Guide to Road Safety Part 8: Treatment of Crash Locations (Austroads 2009a – under review)
  • Guide to Road Design Part 4: Intersections and Crossings – General (Austroads 2009b – under review)
  • References
  • Appendix A Rear-End Crash Contributory Factors from Austroads (2009a)
  • Appendix B Rear-End Crash Countermeasures from Austroads (2009a)
  • Appendix C Urban and Rural Road Environment Classification Rules
  • C.1 Rules as a Decision Tree
  • C.1.1 New South Wales, Victoria, Western Australia, South Australia and Northern Territory
  • C.1.2 Queensland and Tasmania
  • C.1.3 Australian Capital Territory
  • C.1.4 New Zealand
  • C.2 Data Definitions Used
  • Appendix D Sites Selected
  • D.1 New South Wales
  • D.2 Victoria
  • D.3 Queensland
  • Appendix E List of Fields Included in Site Inspection Spreadsheet