Introduction
In my last post I referred to the development of documents on road geometric design standards prepared around 2002 for Kazakhstan through an ADB-funded project.The documents produced don’t seem to have been successfully accepted.
In 2022 the UK’s TRL was asked to review the Road and Bridges Design Manual – Part 1A:Geometric Design (2009) prepared for Kenya by international consultants, this time through an EU-funded project. The draft submissions by the consultant, made in 2009, were reviewed by a National Steering Comittee in Kenya but were not adopted. TRL’s 2022 report (Ref. 5259) was somewhat critical of the 2009 documents.
So this looks like two examples of road design standards / manuals, prepared by international consultants, but where the standards were not found good enough.
TRL’s project to look at the Kenya manuals also involved the preparation of new documents. In their detailed notes, the TRL report said “ The next step, for each of the proposed (new manuals), and the SRBC, was to develop an idealized framework of the contents”, and “the Consultant and the TTF undertook a preliminary review exercise to establish a new manual structure and coding system for Kenya”. Theoretically what is good for Kenya could be good for other countries, and the TRL’s new manual structure and coding system could be of interest elsewhere.
The new manuals have not yet been released (July 2023) but are likely to be published shortly.
Commentary
- The two examples, of unsuccessful road geometric design standards are a cautionary indication that not all documents which have been published as road geometric design standards, are necessarily good material.
- I think it is time that the structure of road geometric design manuals should be changed, but more drastically than the TRL idea, and that manuals should be prepared on a parameter basis.
References
Ref. 5259 Consultancy Services for Review and Updating of Road Design Manuals and Standard Specifications for Kenya Ref. No. KENHA/PCS/342/2021, Draft review report November 2022
Comparative Geometrics 