Road design
 Publication no: AGRD0316
 ISBN: 9781925451245
 Published: 28 September 2016
 Edition: 3.2
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Guide to Road Design Part 3: Geometric Designprovides 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; crosssection 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 3.2 of the Guide provides corrections to:
 Section 3.4.2 Intermediate Speed Rural Roads
 Section 4.8.7 (Table 4.18: Exclusive bicycle lane dimensions in urban areas)
 Section 7.8, (Table 7.12: Minimum radii with adverse crossfall)
 Reference list
 Appendix H (Figure H3: Variation of friction factor with speed)
Edition 3.1 of the Guide corrects Table 8.11: Minimum length vertical curves for reconstruction.
Edition 3.0 of the Guide contains minor editorial and technical changes throughout. Key new information and updates are:
 Section 1.4: Additional information and expansion on the design objectives.
 Section 2.2: Additional information on vulnerable road users, particularly motorcyclists (Section 2.2.4) and new information on emergency aircraft runway strips (Section 2.2.8).
 Section 3.5: Guidance for determining desired speed for rural roads and on steep grades (Section 3.5.1 – 3.5.4).
 Section 4.2: Additional guidance on crown line (Section 4.2.3) and rural road lane and shoulder widths (Section 4.2.6).
 Section 4.3: Additional guidance on shoulder widths and sealing (Section 4.3.3 – 4.3.4).
 Section 4.4: Additional guidance on verge slopes (Section 4.4.2) and rounding (Section 4.4.3).
 Section 4.8: Additional information on providing bicycle lanes (Section 4.8.4 – 4.8.12).
 Section 7.7: New guidance on a procedure for designing superelevation (Section 7.7.1) and development of superelevation on shoulders (Section 7.7.12).
 Section 8.2: New information outlining a procedure for checking critical vertical clearance points (Section 8.2.2).
 Section 9.9: Additional guidance on selecting a starting and terminating point of an auxiliary lane Section 9.9.1.
 New Appendices:
 Appendix B: Emergency aircraft runway strips
 Appendix E: Narrow median treatments with wire rope safety barrier
 Appendix F: Guidance for wide centreline treatments
 Appendix G: Flowcharts and table for determining stopping sight distance requirements for curves with barriers.


 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



 4.8.1 General
 4.8.2 Road Geometry
 4.8.3 Gradients
 4.8.4 Crosssection and Clearances
 4.8.5 Separated Bicycle Lanes
 4.8.6 Contraflow Bicycle Lanes
 4.8.7 Exclusive Bicycle Lanes
 4.8.8 ‘Peak Period’ Exclusive Bicycle Lanes
 4.8.9 Sealed Shoulders
 4.8.10 Bicycle/Car Parking Lanes
 4.8.11 Wide Kerbside Lanes
 4.8.12 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







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