Study of Sedimentation and Consolidation of Soil Particles in Dredged Slurry

Sedimentation and consolidation of soil particles in dredged slurry is very complex since there are no explicit rules. A modified experiment method - multilayer extraction sampling - is adopted in this study. The volume distribution of soil particles can be determined first, and the average velocity of soil particles for different size groups of soil particles is calculated using the volumetric flux function method. The result reveals that there are three different zones existing during the sedimentation and consolidation of soil particles in dredged slurry -hindered settling zone, flocs compression settling zone, and consolidation zone. During the first hour and the following 6 hours of preliminary sedimentation period, the velocity of soil particles is much smaller than the velocity calculated from Stokes equation in the hindered settling zone. There is no relative displacement of soil particles in flocs compression settling zone and self-consolidation zone. All soil particles in these two zones belong to the sediments. The density of flocs compression settling zone is about 1.04 g/cm³ in the experiment.