Method to Calculate Impact Force and Impact Time of Two-Phase Debris Flow

Debris flow was simplified as two-phase liquid composed of particles with the same diameter and slurry with the same mechanical features.Assuming that debris flow was one dimension liquid moving to one direction.Authors established methods to calculate impact forces of liquid phase and solid phase by the second Newton's law through calculating velocities and acceleration of every phase,then,obtained general equation to calculate impact force of debris flow.Further,method to calculate total impact time of debris flow through impact formalities,such as impact pits in surface of control structures and impact troughs in bank of debris flow valley was obtained.According to engineering cases to control debris flow,it is obvious that the results between calculating in the methods and observations in real-time field are fitted better,whose relative errors are in 3%,which are permitted in engineering design.