EXAMINATION OF THE DISASTER PROCESS OF REVETMENTS IN THE HIKOSAN RIVER AT KYUSHU-HOKUBU HEAVY RAIN IN 2014

Abstract

The disaster process of revetments in the Hikosan river at Kyushu-hokubu heavy rain in 2014 was examined through the temporal variation of river channel, a field survey and numerical simulation of flood flows. The temporal change of bed level, positon of deepest bed level and low flow channel were obtained from cross-section. The maximum and time integrated velocity, friction velocity were obtained by distributed hydrological model for rain-fall runoffs in watershed and 2D unsteady free-surface flow model based on flux-difference splitting scheme and unstructured finite-volume method for flood flows in the river were used for the numerical simulation. Through these results, damage process of revetments were examined.