2014 年 20 巻 p. 379-384
Unprecedented heavy rainfall occurred in Yamaguchi and Shimane Prefectures on July 2013. These regions suffered severe damage brought by floods during the rainfall. In order to investigate the characteristics of the damage and the mechanisms of land erosion by the floods, post-disaster survey and numerical simulation were conducted for Abu River in Yamaguchi along which three railway bridges were washed out and soil in agricultural lands was intensively eroded. The results of the field observations and the two-dimensional flow analysis indicate that the overflow at a meandering point of the river caused land erosion, and the strong flows were induced at the points where one of the railway bridges was washed out.