土石流シミュレータを用いた土石流発生時の避難経路の検討

Abstract

To prevent losses of human life caused by sediment disaster, the warning and evacuation system have been advanced. To obtain information of the safety evacuation route and shelter from debris flow, we applied debris flow simulator Hyper KANAKO system to a debris flow prone torrent in Kyoto Prefecture. In this study, we set landform data using digital elevation data. We also changed the landform partly to consider the artificial channel depth and building height. We set the supplied hydrograph using assumed rainfall intensity (88.9 mm/h) from Iwai’s method. We set recurrence intervals of the assumed rainfall intensity as 100 years. Sediment volume of debris flow was estimated from assumed slope failure area rate (5%) and depth (1.5 m). The simulation results showed that part of the sediment moved down through the channel and sediment overflowed where channel becomes shallow. The results also showed that the flooding flow concentrated in the passageway under railroad which is narrow and located low.