Experimental study on sedimentation and consolidation of soil particles in dredged slurry

Abstract

Sedimentation and consolidation of dredged slurry is very complex in practice. A new Multilayer Extraction Sampling (MES) method was developed in this study to better understand the underlying law of sedimentation and consolidation of soil particles in slurries. Comparing with previous methods, the advantages of this method include: (1) the equipment is easy to operate and the test procedures are simple; (2) the volume distribution and the settling velocity of soil particles can be measured and calculated by Volume Flux Function (VFF) approach at different time and heights during sedimentation and consolidation process; (3) soil formation from sedimentation of dredged slurry can be also further studied based on pore water pressure measurements in conjunction with the velocity and density distributions. The experimental results revealed that there were four different zones during sedimentation and consolidation process: water zone, hindered settling zone, consolidation zone and a new zone termed as “transition zone” where soil particles are in contact with each other but effective stress are not fully developed. It is concluded that the sedimentation and consolidation of soil particles in dredged slurry was studied successfully in a holistic manner using this new experimental method.