Study of Sedimentation and Consolidation of Soil Particles in Dredged Slurry

摘要

Sedimentation and consolidation of soil particles in dredged slurry is very complex since the rule of it is not explicit. A modified experiment method called 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 group of soil particles is calculated using volumetric flux function method. The result reveals that: there are three different zones existing during the sedimentation and consolidation of soil particles in dredges slurry. They are 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 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 1.04g/cm~3 in the experiment.