Road design

Cover of Guide to Road Design Part 4C: Interchanges
Guide to Road Design Part 4C: Interchanges
  • Publication no: AGRD04C-15
  • ISBN: 978-1-925294-85-9
  • Published: 7 December 2015
  • Edition: 2

Guide to Road Design Part 4C: Interchanges provides guidance on the geometric design of interchanges on freeways/motorways and on major arterial roads.

The Guide covers the design of interchanges between: freeways and arterial roads; two freeways; and two major arterial roads.  It covers the geometric design of all the elements of an interchange including the: alignment and cross-section of the freeway in the vicinity of the interchange, the intersecting road and the ramps; merge and diverge ramp terminals at the freeway; and ramp terminals at the intersecting road.

Edition 2.0 contains minor editorial and technical changes to Sections 1.3, 1.4, 1.8, 3.2, 4.9 (new), 9.2, 10.1, 11 and 17.3. Updates have been made throughout this edition to include new and updated reference material and cross-references to other Guides, including:

  • Section 1 Introduction: updates to road safety including the Safe System principles; and additional information on design objectives and staged development.
  • Section 3 Forms of Interchange: additional information on factors that may influence the type of interchange.
  • Section 4 Structures: additional section providing information on safety screens.
  • Section 9 Vertical Alignment: additional information on criteria to be considered for grading at a cross-road.
  • Section 10 Ramp Terminals at Major Roads: amending the longitudinal grade of a minor road to not exceed 2%.
  • Section 11 Ramp Terminals at the Major Road: additional information to expand the range of speeds shown in Table 11.2 and Table 11.3.
  • Section 17 Other Considerations: additional section on oversized and high wide load corridors.