| Most national highways in rural parts of Hokkaido are two-way two-lane roads. In these highways、 passing maneuvers using oncoming lanes are frequently observed. Such passing is even observed when road surfaces are covered with compacted snow in the snowy season. In the implementation of measures to optimize speed and safety on a certain road、 it is necessary to conduct traffic simulations on passing maneuvers using the oncoming lane of a two-way、 two-lane highway. However、 there have been no traffic simulations on passing maneuvers with consideration of conditions on winter surfaces covered with snow and ice or poor visibility caused by snowfall、 fog and other factors.[*]In this study、 a traffic simulation to model passing maneuvers was created using values measured in a passing-maneuver field study conducted on a two-lane highway in summer and winter. The field values for the number of passing maneuvers、 traffic volume and speed distribution were compared with the simulation results. The outcomes confirmed that the difference between them was small. The sensitivity analysis results revealed that the number of passing maneuvers when the surface is covered with compacted snow and visibility is poor does not increase as much as that on the dry surface even when the traffic volume in the original lane becomes higher. The passing success rate tended to decrease with higher volumes of traffic in the oncoming lane regardless of surface conditions. |
