URBAN ROAD DESIGN AND ARCHITECTURE

This report by a Working Group of the PIARC Committee on Urban Areas (C10) suggests the development of further ideas on the organisation and design of urban road networks, following the Committee's recent report on urban road network design. The Group aims to: (1) develop the Buchanan Report's concept of 'environmental capacity'; (2) explore the better integration of functional and visual aspects; and (3) focus on main roads, other than motorways, by developing the concept of 'urban boulevards' for main arterials integrated in their urban environment. The report first discusses the road as a structuring element of urban areas, and some of the interactions between roads, urban development, and environmental impact. 'Environmental capacity' may be defined as the level of traffic that people can tolerate, up to the point where urban functions and quality of life are perceived as strongly reduced. A proposed method of analysing environmental capacity and problem zones is developed, and its applications are indicated. Some design criteria for major urban arterials are considered. The report's concepts are applied to specific urban situations in: (1) Madrid, Spain; (2) Dijon, France; (3) Montreal, Canada; and (4) Melbourne, Australia.