Road Design
- Publication no: AGRD03-16
- ISBN: 978-1-922382-15-3
- Published: 26 February 2021
- Edition: 3.4
- Superseded
- PDF (free) Download
Guide to Road Design Part 3: Geometric Design provides road designers and other practitioners with information about the geometric design of road alignments.
Design parameters include: road classification; design speeds; design vehicles; alignment controls; cross-section components, including travel lanes, shoulders and verges; and provisions for public transport and cyclists.
Speed parameters include: operating speed, desired speed and design speed; and their relationship with each other.
Horizontal and vertical alignments include development and application of: circular curves; superelevation; grades; vertical curves; procedures for the grading of a road alignment; and determination of sight distances across vertical curves.
Edition 3.4 has been superseded. The latest edition is available here.
Edition 3.4 of the Guide contains minor editorial and technical changes throughout to reflect new Austroads research and provide further clarification and examples for designers.
- Section 1.51: Examples of mid-block treatments that are consistent with the Safe System objectives
- Section 2.2.3 , 4.1, 4.12.2: Citing new Austroads research
- Section 2.2.7: Guidance to designers about the design and check vehicle and being appropiate for classification and function of the road.
- Section 3.1: Advice to consider vehicle speeds on approaches to intersections
- Section 3.2.5: Additional speed parameters
- Section 4.2.5: Additional information regarding narrow lanes
- Section 4.6.4: Further guidance on appropriate type and placement of kerb and channel
- Section 4.7.2: Advice on using WCLT and WRSB treatments
- Section 4.8: New section on footpaths
- Section 4.11.2 and 4.11.3: Guidance on parallel and angel parking
- Section 4.13.3: Further information on bus stop waiting areas
- Section 6.1: Information about reviewing alignments and modifying designs of uncoordinated horizontal and vertical geometry
- Section 6.2: Further safety considerations which includes steep or prolonged downhill gradient
- Section 7.1: Advice to designers about horizontal alignment
- Section 7.5.1: Clarification on compound curves
- Section 7.9: Further research reference on information on the benefits of widening on horizontal curves
- Section 8.5.2: An additional aspect to the design of grades that can be adopted in difficult terrain:
- Section 8.5.5: Further considerations for steep grade
- Section 9.6.2: Further information regarding the effects of slow vehicle turnouts
- Appendix B: New Appendix on mid-block treatments for Safe System speeds
- Commentary 7: Further research referenced on shoulder width vs safety
Superseded editions:
Edition 3.3 published April 2020
Edition 3.0 published September 2016
- 2.2.1 Location
- 2.2.2 Road Classification
- 2.2.3 Traffic Volume and Composition
- 2.2.4 Vulnerable Road Users
- 2.2.5 Design Speed and Operating Speed
- 2.2.6 Alignment Controls
- 2.2.7 Design Vehicle
- 2.2.8 Use of Roads as Emergency Aircraft Runway Strips
- 2.2.9 Environmental Considerations
- 2.2.10 Access Management
- 2.2.11 Drainage
- 2.2.12 Utility Services
- 2.2.13 Topography/Geology
- 4.9.1 General
- 4.9.2 Road Geometry
- 4.9.3 Gradients
- 4.9.4 Cross-section and Clearances
- 4.9.5 Separated Bicycle Lanes
- 4.9.6 Contra-flow Bicycle Lanes
- 4.9.7 Exclusive Bicycle Lanes
- 4.9.8 ‘Peak Period’ Exclusive Bicycle Lanes
- 4.9.9 Sealed Shoulders
- 4.9.10 Bicycle/Car Parking Lanes
- 4.9.11 Wide Kerbside Lanes
- 4.9.12 Supplementary Treatments
- 7.7.1 Superelevation Design Procedure
- 7.7.2 Linear Method
- 7.7.3 Maximum Values of Superelevation
- 7.7.4 Minimum Values of Superelevation
- 7.7.5 Application of Superelevation
- 7.7.6 Length of Superelevation Development
- 7.7.7 Rate of Rotation
- 7.7.8 Relative Grade
- 7.7.9 Design Superelevation Development Lengths
- 7.7.10 Positioning of Superelevation Runoff without Transitions
- 7.7.11 Positioning of Superelevation Runoff with Transitions
- 7.7.12 Superelevation Development on Shoulders
- 7.7.13 Development of Superelevation to Avoid Drainage Problems
- Appendix A 3.1 Application of EDD for Stopping Sight Distance
- Appendix A 3.2 Base and Check Cases
- Appendix A 3.3 Vertical Height Parameters
- Appendix A 3.4 Driver Reaction Time
- Appendix A 3.5 Longitudinal Deceleration
- Appendix A 3.6 EDD Stopping Sight Distance for Cars
- Appendix A 3.7 Shoulder/Traversable Widths and Manoeuvre Times
- Appendix A 3.8 EDD Crest Vertical Curve Size
- Appendix A 3.9 Sight Distance Requirements on Horizontal Curves where there is no Line of Sight over Barriers/Structures
- Tables
- Figures