Journal of Natural Disaster Science

NUMERICAL SIMULATION OF FLOODING AND DAMAGE TO HOUSES BY THE YOSHIDA RIVER DUE TO TYPHOON NO.8610

Satoshi SATO
Engineer, Tohoku Electricity Co.
Fumihiko IMAMURA
Research Associate, Faculty of Engineering, Tohoku University
and
Nobuo SHUTO
Professor, Faculty of Engineering, Tohoku University

(Received 9 September, 1989 and revised form 11 December, 1989)

Abstract

The shallow water theory was applied to hindcast a flood which flowed through breaches in river dikes and inundated reclaimed lowland. Methods are proposed to determine hydraulic resistances for houses, roads, footpaths in paddies and rice plants instead of the conventional method of assuming bottom friction in terms of Manning's roughness.

Numerical results are compared with actual damages done to houses. The hydrodynamic force of Aida and the turning moment of Takahashi et al. are shown to be useful for indicating the degree of damage, except for in the immediate vicinity of breaches where the shallow water theory does not give a good approximation.

Key words

flood, numerical simulation, roughnrss, hydraulic resistance, damage to houses