An Analysis of Bicycle Travel Speed and Disturbances on Off-street and On-street Facilities

For transport planners and land use practitioners, many are the qualitative guidelines provided regarding the location and quality of separated bicycle facilities. When separated bicycle facilities are poorly designed or placed in less than optimum locations, their intended use is less than anticipated. An interesting element in the evaluation of bicycle facilities that have received less attention revolve around the disturbance due to the presence of other users on cyclists way. Other users consists in cyclists and pedestrians for off-street bicycle facilities, and motorized vehicles on the roadway. This study focuses on quantifying the role of disturbances encountered on separated cycling facilities, compared to disturbances from cycling mixed with traffic, assuming cyclists speed as a performance measure and analysing the cyclist speed reductions from different types of disturbances. Collecting data on three segments of Bologna's cycling network (Italy), we measured the frequency, type, and speed reduction attributed to different types of disturbances. The data collected shows that pedestrian disturbances on the separated facility are highly frequent but associated with moderate speed reductions, while disturbances in the mixed traffic environment can be relatively fewer but have more severe speed reductions. Moreover, our results suggest that design elements of separated facilities can play a role in affecting the frequency, type, and severity of disturbances. This work helps lay the foundation for outlining the existing relationship between bicycle travel speeds and non stationary disturbances.