JDR Vol.8 No.6 pp. 1090-1095
doi: 10.20965/jdr.2013.p1090


Wind Speed of Tornado to Make a Road Damage

Minoru Noda and Fumiaki Nagao

*The University of Tokushima, 2-1 Minami-Josanjima, Tokushima 770-8506, Japan

July 12, 2013
October 16, 2013
December 1, 2013
tornado disaster, windborne debris, adhesion strength

Three tornadoes almost simultaneously hit the northern Kanto region north of Tokyo, Japan, on May 6, 2012. One peeled away and scattered asphalt 4 m wide, 30mlong and 50mmthick from roads in Tochigi prefecture. According to the Japan Meteorological Agency, the F scale of this tornado was between F1 and F2. A few F1-F2 tornadoes occur in Japan each year, but the scale of road damage following an F1-F2 tornado has not been previously observed. To determine the wind speed behind this road damage, a new approach was adopted focusing on the speed of flying debris and the pressure drop. The resulting determined a wind speed of approximately 100 m/s.

Cite this article as:
Minoru Noda and Fumiaki Nagao, “Wind Speed of Tornado to Make a Road Damage,” J. Disaster Res., Vol.8, No.6, pp. 1090-1095, 2013.
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Last updated on Feb. 25, 2021