Road closures occurred as much as 4,200 times in 1997 alone on the expressways in Japan with a total duration of 26,000 hours (total duration of road closures caused on both up and down lines for each section). 65 percent of road closures are caused by weather-related reasons, with 42 percent of those being attributed to poor visibility. Half of poor visibility-caused road closure is due to fog. Since fog-prone areas are limited, it may be possible to establish comprehensive measures to prevent road closures due to fog. This report covers the results of a study which investigated the effects of traffic control based on ITS technologies as well as conventional measures to prevent road closure due to fog. The ITS-based traffic control system was tested on two expressway sections where road closure frequently occurs due to fog, and it was found that such technologies could yield favourable economic effects.
Samenvatting