Prediction of Debris Folw Hydrographs

Abstract

When we discuss the effect of debris flow control structures or when predict debris flow prone areas, it is necessary to predict debris flow hydrographs. Many data of debris flow hydrographs have not been collected so far. At Hunshui Gully in China intensive observation was carried out in the late 1970's. These data are analyzed. Some characteristics of debris flow hydrographs have been made clear; runoff rate, the coefficient of peak discharge and the relationship between sediment discharge and water discharge. A rainfall-runoff model was applied to explain debris folw hydrographs. Most debris flow hydrographs can be explained by the method. Debris flows of large peak discharge, however, can not be explained. It is considered that some natural dams appeared dne to landslides and collapsed in those cases from comparing observed and calculated hydrographs.