学会誌「自然災害科学」

自然災害科学55 Vol.19,No.3, 2000

【報告】[Scientific Report]

平成10年8月豪雨による阿武隈川上流域の河川災害

River Disasters at the Upstream Reach of the Abukuma River in Fukushima Prefecture due to Heavy Rainfall in August 1998

辻 聡太*・三輪 弌**・永吉 武志***

Sota TSUJI*, Hajime MIWA** and Takeshi NAGAYOSHI***

Abstract

A number of river disasters took place at the upstream reaches of the Abukuma River in Fukushima Prefecture due to heavy rainfall in August 1998. River channel changes before and after flooding were studied through the comparative investigation of aerophotos. Actual disaster conditions were observed through field surveys as well. The mechanisms and causes of these river disasters were clarified as: (1) bank erosion and the failure of protective works that occurred near river banks which had been struck by the main flow during flooding, (2) surface erosion of high water channels in compound cross-sectional reaches by divisions of the main flow that ran into the channels, and (3) the destruction of weirs and the failure of banks in downstream sections of weirs mainly due to degradation of the river bed.

キーワード:

阿武隈川，河川災害，蛇行，交互砂州，洪水水衝部，航空写真比較判読

Key words:

Abukuma River, river channel disaster, river meander, alternate bar, attacking bank of flood flow, aerophoto investigation
*
日本工営
Nippon Koei Co. Ltd.
**
岩手大学農学部
Faculty of Agriculture, Iwate University