Traffic Operations at an Entrance Ramp of a Suburban Freeway First Results

Within the general framework of updating the French design guidelines for urban freeways, some studies are conducted for building of a new model for traffic operations at on-ramps. One of them, described in this paper, aims to gather general knowledge on the merging process, from the analysis of microscopic traffic data collected on an instrumented suburban freeway segment. This equipment delivers vehicle trajectories, sampled at a 50 m interval. In a first step, empirical evidence on lane use and operating speeds has been established. Then, vehicles interactions have been studied, so as to compute risk indicators at merging locations, and to model the merging probability as a function of the traffic environment. On-going works and perspectives are presented to conclude.