Evaluation of City Planning Road Development Measures by Microscopic Traffic Simulation

This study was made on the development plan of Kawahara Avenue, a road project authorized in city planning of Miyazaki City in Japan. The Kawahara Avenue development is planned along the Oyodo River. The land use of the area along the route comprises the tourist hotel zone, residential zone, and industrial zone. The Kawahara Avenue planning, unlike most other road development plans in Japan, requires much more than simply providing for the smooth flow of traffic. In the tourist hotel zone where the leading Miyazaki City hotels are located, the image and impression the tourists may have about the city is an important consideration. Therefore, the city government intends that this section of the road should not have excessive traffic. In the residential zone, the existing road network consists of narrow streets with no sidewalks. In addition to the sidewalks to be built, Kawahara Avenue is expected to handle a great deal of the traffic passing the residential district. This should help meet the goal in providing a safe environment for the pedestrians in other narrow streets without sidewalks. Under the circumstances as stated above, the planning has faced significant constraints in land purchasing involving forced move-out in the result of financial problems and coordination of the views between the city administration and the residents in the vicinity. The purpose of this research is to study under the given constraints what would be the most appropriate plan for the development of Kawahara Avenue. First, a traffic monitoring survey was conducted in the subject districts to compile Origin-Destination (OD) data of traffic flow in the districts. Then, the road network of the subject districts and traffic signal phase data were digitized to carry out microscopic traffic simulation and checked for reproduction accuracy of the current situation. The results confirmed that simulation reproduces the traffic conditions of the districts with sufficient precision. Furthermore, we prepared several hypothetical proposals for the road development and evaluated with the same simulation system as to how the traffic situations would be had those proposals been implemented. As a result it was demonstrated that the original goals can be achieved by developing the road within the given constraints.