Processes of urban change : planning and monitoring strategies through the application of the fringe belt model to Nantes and Rennes, France

In the contemporary context of globalisation, the international structure of cities is changing. This paper is aimed to understanding the processes of urban change to a morphological point of view, and to proposing new methodologies in monitoring urban forms of tomorrow. Is it absurd to preserve urban density ?To identify and analyse the urban growth dynamics and the resultant urban forms at the intra-urban scale, this study is based on the fringe belts model, tested on two French cities, Rennes and Nantes. The model stresses the alternance of high and low density zones. This quiet traditionnal theory, using topics such as density, size, heterogeneity, historical background, is adjusted with the use of GIS and new questionnings to be put in perspective with the issue of the « Renouvellement urbain » in France. The recent law on Urban Solidarity and Redevelopment (August 2000) encourages compact city policies, calling the fringe belts areas into question. In this frame, the application of the model in France, through theoretical and empirical investigations, makes the current urban form of Rennes and Nantes understandable and comparable. The role of the public authorities in the spatial dynamics is questionned. As a result, we must conclude that for the moment, the fringe belts are rarely taken in account as entities by planners. Thus, the model could be diffused and used as an efficient planning tool to elaborate urban strategies and politics of urban form development.