Measuring the hindering effect of intersections on walkability. A practical application to urban crossing in the city of Alghero

In this paper a ranking method of urban intersections based on their hindering or facilitating effect on walking is proposed and tested on a sample of street crossings in the city of Alghero. The study investigates the effects of geometric and operational characteristics of urban intersections on pedestrian accessibility. Tthrough a detailed audit conducted on each node we collected a set of micro level data on the impact of intersections on wakability expressed by pedestrian: the comparison between objective and subjective information allowed to identify the most important influencing factors and their relative weight in the measure of walkability. Then we proceeded to classify intersections: the variety and diversity of attributes suggested the employment of a multicriteria ranking evaluative method: more precisely, we adapted the ELECTRE TRI rating method (Roy and Bouyssou, 1993) with the purpose of rating urban opportunities according to their influence on walking.