洪水流の縦断水面形変化と準三次元流解析法を用いた石狩川河口部の洪水中の河床変動解析

抄録

In this paper, the numerical analysis of the unsteady quasi-three-dimensional flow and the bed variation using the observed temporal changes in water surface profiles is conducted to elucidate the characteristics of the flood flow and the bed scouring during the 1981 flood in the Ishikari River mouth. This analysis enables to verify the reproducibility of bed variations over time during floods by calculating the temporal changes in water surface profiles to coincide with observed one. The transportation of suspended load in the flood flow is evaluated by the three-dimensional advection-diffusion equations of suspended load concentration calculated with the vertical distributions of velocities, which are obtained from the unsteady quasi-three-dimensional flow analysis.