Analysis of the Influence of Sport Cyclists on Narrow Two-Lane Rural Roads Using Instrumented Bicycles and Microsimulation

It is frequent to see cyclists on Spanish two-lane rural roads, both riding individually and in groups. However, these roads were designed only for motorized vehicles, most of them having a narrow section with a null or impassable shoulder. Currently, drivers and cyclists have to share roads and interact, affecting both safety and traffic operation. The possibility of overtaking offers an improvement in traffic operation, however on narrow roads it can be difficult, meaning a greater invasion of the opposite lane thus creating more dangerous situations and implying a higher overtaking duration. To analyze the phenomenon, field data from instrumented bicycles and naturalistic videos were collected, then some performance measures to characterize safety and traffic operation were obtained. To increase the number of overtaking manoeuvres and performance measures obtained from observations, microsimulation has been used by adapting a model to include cyclists and their interaction with motorized vehicles. The traffic microsimulator was calibrated and validated with field data. The results show that cycle traffic presence decreases motorized vehicle average travel speed and increases percent followers and delays. Microsimulation can be used to study other traffic scenarios and can help road administrations to safely and efficiently integrate cyclists to vehicular traffic on rural roads.