In the investigation, a methodology for the application of microscopic traffic simulation to estimating the level of service on freeways consistent with the German Highway Capacity Manual HBS was derived. Traffic flow on standard types of freeway segments were modeled with the simulation tools BABSIM, VISSIM, Aimsun, Paramics, and SUMO. The simulation models were calibrated based on the HBS design values. The capacity was determined by identifying traffic breakdowns in the simulation, which were induced by increasing the traffic volume to 120 % of the HBS design capacity. At merge and diverge segments, six different proportions of the ramp volume were analyzed. To evaluate whether the simulation results match the HBS design values, a maximum deviation of 5 % was used as target value. With the tools BABSIM, VISSIM, Aimsun, and Paramics, the maximum error was undercut in most cases, whereas larger deviations were obtained with the tool SUMO. The transferability of the calibrated simulation parameters to freeway segments with geometric and traffic parameters beyond the boundary conditions of the HBS was proven based on field data. As a result of the investigation, recommendations and standard parameters for the simulation of freeway traffic flow are provided. (Author/publisher)
Abstract