Incipient Motion Law of Cohesive Soil and the Mixture of Cohesive Sediment and Coarse Particle

The incipient motion of cohesive sediment and the mixture of cohesive sediment and coarse particle are researched systematically. On the basis of turbulent flow theory, a formula for determining the critical shear stress of cohesive sediment with the Bingham stress of cohesive sedi ment is ascertained. According to a series of experiments, the conditions of incipient motion for the mixture of cohesive sediment and coarse particle in different cases are discussed and formalized. The result of all above-mentioned formulae are in agreement with experiment data. In addition, a qualitative analysis about the conditions of incipient motion of cohesive sediment and the mixture of cohesive sediment, and coarse particles above which dense flow exista are carried out.