Austroads Road Design

Austroads

Guide to

Road Design

Dr Owen Arndt

Overview

The Guide to Road Design Series:

 Is a set of comprehensive guides to promote safe, economical and efficient road designs

 Covers most aspects of road design, including

– Geometric elements

– Drainage

– Roadside features

 Is intended to replace guides from individual jurisdictions

– Promote standard practice

– Avoid duplication

– Companion documents may be developed to cover specific local design situations

 Is closely related to the Guide to Traffic Management Series

– Needs to be considered in conjunction with all of the other Austroads guides

Guide to Road Design – structure

Part 1 Introduction to Road Design (23 pages)

Part 2 Design Considerations (38 pages)

Part 3 Geometric Design (298 pages)

Part 4 Intersections and Crossings – general (144 pages)

Part 4A – Unsignalised and Signalised Intersections (235 pages) Part 4B – Roundabouts (102 pages) Part 4C – Interchanges (110 pages)

Part 5 Drainage Design (210 pages)

Part 6 Roadside Design, Safety and Barriers (284 pages)

Part 6A – Pedestrian and Cyclist Paths (113 pages) Part 6B – Roadside Environment (102 pages)

Part 7 Geotechnical Investigation and Design (81 pages)

Part 8 Process and Documentation (72 pages)

Organisations Represented

 State road authorities (6 members)  Territory road authorities (2 members)  New Zealand Transport Agency

 Assocation of Consulting Engineers, Australia  Australian Bicycle Council

 Australian Local Government Association

 ARRB

 Organisations represented here will be the users of the guide

(potentially anyone undertaking road design in Australia and New Zealand)

Development of the Guide

Source material

 Existing Austroads guides where the material is still up to date and relevant, including

– Urban & Rural Road Design Guides

– Guide to the Hydraulic Design of Bridges, Culverts & Floodways

– Several of the Guides to Traffic Engineering Practice  eg Parts 5, 6, 13 & 14

 State road authority documents, where material is more up to date  Other documents

– eg Storm Drainage Design in Small Urban Catchments  Some new material developed

Authors

 ARRB

 Particular state road authority members  Consultants

Process

Author / revise draft document

Panel members review and provide comments

Major comments are discussed at panel meeting

Document sufficiently complete No Yes

Seek endorsement

Format of the Guide

 Body contains the bulk of the design criteria

 Appendices contain additional design criteria & examples  Commentaries contain supporting material / background

information

 Material in one place only ie not duplicated between parts or between other series

Format of the Guide

For Parts 3 and 4 (the bulk of the geometric design criteria)

 Values / criteria suitable for new roads (greenfield projects) placed in body

– Normal Design Domain

 Values / criteria generally only suitable on existing roads (brownfield projects), where technically justified, placed in Appendix A

– Extended Design Domain

 No guidance provided for the design of existing roads

(brownfield projects) where Extended Design Domain criteria cannot be achieved

– Design Departures / Exceptions

What’s new

Part 3 - New criteria for minimum size sag vertical curves, adapted from VicRoads

• Use of ‘K’ values exclusively through the guides

What’s new

Part 3 - New criteria for application of superelevation

What’s new

Parts 3 & 4 - Improved guidance on public

transport facilities, from

• VicRoads

What’s new

Parts 3 & 4 - Updated sight distance models based on work from Qld DT&MR

• New ‘constant’ deceleration rates

• New vertical height constants

• More emphasis on designing for trucks

• Additional guidance for sighting over and around roadside

What’s new

Parts 3, 4 and 6 - Additional criteria for on-road and off- road cycle facilities, based on RTA and VicRoads work

What’s new

Part 4B - Additional methods to

provide for cyclists through roundabouts eg physical separation through use of concrete splitter islands, based on RTA work Concrete splitter island

What’s new

Absolute Desirable Absolute Desirable

≤40 b ₅ d _{10 8 12 No} 50 b _{8 11 8 12 No} 60 c _{10 12 14 16 No} 70 c _{12 18 18 20 No} 80 c _{14 22 20 24 Desirably} ≥ 90 c _{14 22 20 24 Yes}

Part 4B - Guide for selecting the minimum central island radius for a circular roundabout, based on Qld DT&MR research

What’s new

Part 4B - New criteria for speed control at roundabouts – entry path curvature, based on Qld DT&MR

What’s new

Part 5 - new material on the design of pollution treatments

What’s new

Distance of hazard from edge of travelled way (m) 20 15 10 0 25 0.2 0.6 0.7 0.5 0.3 0.1 5 0.9 1.0 30 Un-divided roads Divided roads

Part 6 - New material on warrants and location of roadside safety barriers, based on research and testing by RTA

What’s new

Part 6B - New material on

environmental aspects of road design eg fauna sensitive road design, noise control

What’s new

Part 7 - Guidance for road designers on geotechnical issues

Part 8 - Guidance for

road designers on design processes and documentation Client Framework of Suppliers Sub- contractors Contractor B Designer Contractor A* ECI Agreement D&C

Promotion of the new guide

 Each local jurisdiction to produce a strategy for transitioning to the new guides. Road designers will be advised through

– Departmental policy and correspondence

 Location of material in hard copy and on local websites

– Promotion at local forums and workshops  Provision of training courses by ARRB

Thanks

 Thanks to

– All road design review panel members

– Authors, including

 Gary Veith (ARRB)

 David Barton (VicRoads)  Bernard Hammonds (RTA)  Rob Grove (WA MRD)

 Owen Arndt (Qld DTMR)

– Project managers, including  Michael Tziotis (ARRB)  David Barton (VicRoads)  Noel O’Callaghan (SA DTEI)  Rob Grove (WA MRD)

 Graeme Nichols (Tas DIER) 