| Section4 ITS deployment progress in Japan |
Provision of safe road environment |
- Frost Prediction System to Assist Measures against Snow Damage
- User Services :10) Improvement of maintenance operations
- Specific User Services :(33) Improvement of road management works
Since the National Highway No. 25 (Meihan Route) carries a large volume of traffic and is an arterial highway cutting through mountainous areas in Nara Prefecture, it is necessary to take swift actions such as imposing traffic regulations and closure to prevent accidents when it snows a lot or the road surface freezes in winter.
This requires the collection of correct meteorological information, so seven observation stations are built along the highway to obtain necessary data in real time. These observation stations, however, are equipped with sensors capable of only collecting the data of the sites where the stations are located, making it impossible to monitor partial freezing in sections in the shade of mountains. The 2-km section between Fukusumi and Ipponmatsu, which has the highest probability of road surface freezing, is fitted with optical fiber sensors (optical thermo radars) capable of measuring air and road surface temperatures at 5-m intervals.
In February 2000, devices for the Frost Prediction System to Assist Measures against Snow Damage were deployed along the highway: the system uses data provided from the Nara Meteorological Observatory and those obtained by such devices as the above-mentioned optical fiber sensors, to assist the spreading of anti-freezing agent at the proper timing, ensure a safe driving environment, and facilitate road management activities. Along with the establishment of a system to predict the time of road surface freezing and to cope with snow damage by using these devices, efforts will be made to develop software for a reliable frost prediction system.
(Nara National Highway Work Office of the Kinki Regional Construction Bureau, Ministry of Construction)
Components of the system
Optical fiber sensors (optical thermo radars) embedded in the road surface detect the road surface temperature and identify locations likely to be frozen.
Go to ITS HandBook
Back to Home