Abstract：In order to investigate grain-size sorting behavior of dredged slurry at high initial water content during sedimentation, a series of sedimentation tests were carried out on dredged slurries, and the grain-size analysis was performed on the stratified samples at the end of sedimentation. The test results indicate that grain-size sorting occurs more easily with the liquid limit and clay content decreasing and with the initial water content increasing. Sorting degree F was proposed to evaluate the degree of grain-size sorting, and the model of the relationship between sorting degree and initial water content was established. Three stages of no sorting stage, sorting degree increasing stage and sorting degree stable stage were included in the model. The differences among three stages are clarified, and the critical water content between two adjacent stages increases with the liquid limit increasing. The range of the critical water content is also given. When the initial stage of dredged slurry is in sorting degree stable stage, the clay fraction exhibits piecewise-linear distribution along the depth and is not affected by initial water content.
2014, Vol. 35 
