Urban form and the costs of daily mobility. The spatialized travel account tool and its application to the Bordeaux metropolitan area[Formes urbaines et coût de la mobilité : une approche à partir du Compte Déplacements Territorialisé de l'agglomération bordelaise]

For analyzing the reciprocal interaction between urban sprawl and car use, research has first focused on the link between urban density and mobility. By looking for a reduction in energy consumption, cities have favoured a compact planning development. Then reflection has broadened from the simple density to the wider, multi-dimensional concept of urban form. This controversy has led to a renewal of analysis in term of the costs of urban growth, notably by comparing the costs of "compact" and "sprawled" development. The idea is to compare the mobility costs of different urban forms. However, most often because of a lack of data, such studies are scarce. This paper suggests an innovative method to compute mobility costs at an infra-urban scale : The Spatialized Travel Account (STA). It is based on the CERTU's travel account methodology at a metropolitan scale. It puts forward an accurate estimate of the mobility costs for each transport mode (individual and public) and for each type of payer (households, firms, local authorities...). In order to test the relationships between mobility costs and urban form, we link the computed costs to morphological characteristics of infra-urban zones, taking in account sociodemographic characteristics of households.