Derivation of Evacuation Routes to Avoid Narrow Road Adopting Physarum Solver

Japan is a country where disasters occur frequently. When disasters occur, people need to escape from their homes to shelters immediately. Thus, it is desirable for them to choose evacuation routes that are faster and safer. In order to derive these evacuation routes, an evacuation route search method adopting Physarum Solver is developed. However, if evacuation routes derived by the method are narrow, safe evacuation may be impossible. For example, collapsed buildings may block the road. Therefore, this study aims to improve Physarum Solver method to derive evacuation routes that take into consideration road width. GIS and DigitalMap (Basic Geospatial Information) were used to determine road width. This improved method evaluates how narrow road width is, and derives several routes considering distance and road width. As a result of applying this method around JR Ishioka Station in Ibaraki Prefecture, most of the derived routes did not include roads less than 3m width. With this method, evacuees can choose several evacuation routes that are safer and faster.