Characteristic of Vehicle and Driver Behavior at Junctions of Deep Underground Expressways

Abstract

In the large metropolitan areas, usage of grounds and shallow undergrounds are becoming more sophisticated and complicated. Therefore, the construction of the expressway using the deep underground is progressing to improve the transportation network. At the junctions of deep underground expressways, from the aforementioned reasons, there are cases where sudden changes in the road shape are concentrated in relatively short sections such as steep slopes from above grounds to under grounds, split or merge points of the rump tunnels, and sharp curves of the ramps. However, the impact of changes in road structures, usage of deep underground, on vehicles and drivers is not understood properly. In this study, by an indoor driving experiment using the driving simulator, we investigated the behavior of vehicles and drivers at junctions of deep underground expressways. As a result, we confirmed the necessity of attracting attention, which is a standard safety measure. Additionally, we clarified where the risk of rear-end accident is high and tried to grasp the factor.