Urban Form from the Pedestrian Point of View: Spatial Patterns on a Street Network

International audienceWith this paper, we propose and test on empirical case studies a new method of analysis of the form of urban fabric from the pedestrian point of view, mixing the relations considered by classical urban morphology with the computational possibilities of geoprocessing. We consider the two main activities that humans do in the space simultaneously: walking and perceiving the urban landscape. As a consequence, we will be able to analyze the interaction between form elements combined with their geometrical description. At the same time, we will stop short of applying the configurational calculus (whether SSx or MCA) and of studying urban form perception as revealed by mental maps of city dwellers (Lynch 1960). Unlike classical urban morphology, we will consider that urban form is not observed on a plan or as an aerial view, but from the pedestrian perspective. A new spatial unit definition will follow: this new space element is determined by the urban network segment (representing human movement and the main channel of perception of urban form) concurrently with its surrounding space limited to a given visual depth. Through this procedure, urban fabric will be defined as spatial patterns filtered through the possible perception of city users. The proposed approach is particularly powerful, as it allows computing on a larger scale and with geoprocessing methods what in previous research had been done manually or limited to a local urban project scale. Expert judgment becomes less crucial in the characterization of urban fabric (an advantage when the study area is a vast metropolitan area) and the bottom-up approach, by identifying spatial patterns through geostatistical analysis of form elements in the context of their surrounding environment, eliminates the problem of statistical analysis on pre-defined administrative boundaries