Road Note 31: Dissemination Guide to the Structural Design of Surfaced Roads in Tropical and Sub-tropical Regions
Published: January 2023
Main topic: Access and infrastructure, Climate change, Roads, Adaptation
Study countrie(s): Sub-Saharan Africa, Low-and middle-income countries, Global, Africa
Written by: Alemgena Araya, Andrew Otto, Angella Lekea, Dr. Theuns Henning, H. Bailey, J. R. Cook, John Rolt, Manaye Ewunetu, Nigel Hewitt
Published by: TRL Ltd
Study type: Guide
Over the past few decades, TRL Limited (known previously as the Transport Research Laboratory) has produced several guides and publications through research funded by the United Kingdom’s Department for International Development. The Overseas Road Note 31 (ORN 31): A Guide to the Design of Bitumen-surfaced Roads in Tropical and Sub-Tropical Countries, was one of the most notable guides produced through this funding. The last revision (4th Edition) of the ORN 31 was in 1993, but in 2022 the guide was revised to produce the 5th Edition, now titled Road Note 31: A Guide to the Design of Surfaced Roads in Tropical and Sub-Tropical Regions.
