DMRB Volume 6 Section 2 Part 4 (TD 39/94) Road Geometry. Junctions. Design of major interchanges (Withdrawn)

Publication Year

1994

Document Status

Withdrawn

Abstract

Recommendations are given on a design methodology and appraisal process for the comparison of alternative solutions. New layouts are provided for major merges and major diverges to allow for three lanes joining or leaving the mainline. Merges and diverges larger than these are unlikely to be required due to the practical and operational limits on the maximum width of the combined carriageway. For dealing with very large turning movements, connection of interchange links to motorway link roads is likely to be required. Therefore the choice of motorway carriageway provision and major interchange layout will be an iterative process. Operational and driveability assessments based on the decisions and manoeuvres required to negotiate alternative interchange layouts are included. Examples of possible layouts, for the expansion, rearrangement or replacement of typical existing interchanges are illustrated, including consideration of connections to motorway link roads.

Document History

Superseded by CD 122 Road layout. Design. Geometric design of grade separated junctions (HE, 2019). DMRB 6.2.4. Design manual for roads and bridges (DMRB).

ISBN

9780115512681

Publisher Information