Abstract
A lot of vehicles pass through the main line road. Therefore, traffic jams occur when the traffic volume of vehicles increases rapidly, such as during commuting hours in the morning and evening. And when a traffic jam occurs, some cars will flow into the surrounding roads which will be as a “loophole”. In a previous study, the authors found that: vehicles that have entered a “loophole” will continue to drive on this road until the “loophole” connects to a road that makes it easier to return to the main line road, even in the section beyond which the traffic jam on the main line road has been resolved. The authors conducted a questionnaire survey of nearby junior high schools to clarify the places where they felt “dangerous”, and compared and collated places where sudden braking occurred using ETC2.0 data or places where traffic accidents occurred using GIS information. As a result, it was shown that the safety of roads designated as "loophole‘’ is declining, even in sections where traffic jam on the main line road has been resolved. However, in previous studies authors did not analyze in detail the following: regarding vehicles passing through the " loophole", the increase or decrease in the number of vehicles returning to the main line road is "linked to the traffic jam situation“ or the velocity of the vehicle traveling through the "loophole", etc.. In this study, as in the previous study, the analysis target was the road that was regarded as a "loophole" parallel to the section of the main road where the traffic jam was resolved. And the authors conducted a detailed analysis of the traffic routes and velocity of vehicles passing through the "loophole'' and the frequency of sudden braking, and evaluated the traffic environment.
