Analisi delle distribuzioni di velocità sulle piste ciclabili e sulle carreggiate stradali adiacenti

When choosing between an off-street or an on-street facility, cyclists consider different factors, among which the most important are safety – or better, perceived risk – and travel speed. The presence of an off-street facility clearly encourages bicycle modal choice, but in case of inconsistency, poor design or a significant pedestrian flow, the user can consider reduced the off-street path’s utility. The present study’s objective was to investigate the correspondence between cyclists’ travel speed and the disturbance due to the presence of other facility users both on a shared off-street path and on a shared on-street lane. Three segments of the cycle network in the city of Bologna were examined, evaluating their percentages of usage and the statistical distribution of cyclists’ speeds. Furthermore, separated measures were made in order to evaluate the decrease of speed caused by the different disturbances that a cyclist can encounter on an off-street path (other cyclists and pedestrians) and on an on-street lane (motor vehicles). Decreased speed and probability of disturbance were thus used to determine a weighted average cyclists’ speed in the two situations, to be compared with the ideal speeds. The results suggest that the bigger disturbance on an off-street path is constituted by pedestrians, and a high pedestrian volume on the facility could induce cyclists to choose to move on the street, even considering the higher risk when sharing the cross section with motor vehicles.