CAPACITY ANALYSIS AND DESIGN PRACTICE FOR UNSIGNALIZED AT-GRADE INTERSECTIONS IN FINLAND

The Finnish design practice for unsignalized intersections is divided into three categories according to the type of road environment: urban, rural built-up, and rural. The Finnish National Road Administration (FinnRA) has worked out design guidelines for each of these categories. In addition, the cities also use guidelines of their own. FinnRA guidelines for at-grade intersections will be updated in the near future. In recent years capacity and design studies have mainly concentrated on roundabouts. As a result, a new type of roundabout has been introduced in the guidelines with good results. In the future one of the main fields in capacity research will be the development and updating of present capacity calculation methods and base values, although no decisions concerning a new capacity model have been made. In addition, simulation of unsignalized junctions will be an important area of research, in which further calibration and validation of the Finnish HUTSIM program will be an essential part.