Simulation Model Applied to Japanese Expressway

In Japanese expressway systems, congestion occurs on many sections around large urban areas. In order to investigate countermeasures for these bottleneck sections, a traffic simulation model is developed which computes traffic flow characteristics and traces the behavior of congestions under given traffic demands. A 24 km study section was selected from Meishin expressway in Osaka where congestion occurs from two tunnels almost every morning during peak period. An extensive traffic survey was conducted making use of aerial photography, video camera recording and floating tests. A simulation model for traffic flow through bottlenecks was developed on the basis of the results of the traffic survey. The expressway bottleneck simulation model was a macroscopic model based upon the theory of compressible fluid. The results of the simulation model are satisfactory. The output from the model shows that the model pursues the behavior of congested areas and that the travel time through the study section computed from the model output agrees with the actual measurements from the floating test.