抄録
In debris flows over erodible beds, kinematic bed conditions such as velocity and velocity gradient are determined from the dynamic condition that the driving force must be equal to the yield stress at the bed surface. On the other hand, debris flows over rigid beds depend on the conditions; bed slope, sediment discharge rate, static friction angle of sediment and friction angle of grain to the bed surface. In present study, the differences between debris flows over erodible beds and ones over rigid beds, and their transitions are clarified theoretically by solving velocity profile, sediment concentration profile and flow resistance and experimentally by using flume data.
