変勾配流路における土石流の形成

Abstract

Prediction of the hydrograph of the debris flow which occurs in an actual watershed neces-sitates the analysis of its formation on varied slope under irregular bed thickness, width, ma-terial, seepage water, and surface water supply conditions. In this paper, authors present thesystem of equations to predict the process. This system is not only able to estimate the hydro-graph of the debris flow at arbitrary position in the channel, but also obtain the change of theconcentration of particles in the flow separating them into coarse and fine components. Applica-tion of this system both to the laboratory experiments and the actual huge mud flow generatedby the eruption of Mt. Nevado Del Ruiz, Colombia, proved that it is a promising method.