Sorting effect is common in the process of hydraulic filling of dredged mud, which inevitably leads to differences in the spatial distribution of mechanical properties of dredged mud. To investigate the influence of the sorting effect on the compression and permeability characteristics of sandy dredged mud during hydraulic deposition, laboratory settling column tests were conducted to simulate the formation of sorted soil samples under different conditions. One-dimensional consolidation-permeability tests were performed to study the compression and permeability behavior of the soil. The experimental results demonstrate that: (1) The sorting effect induces distinct particle stratification within the dredged mud: bottom-layer samples, enriched with coarse particles and depleted of fines, exhibit markedly lower compressibility, nearly linear compression curves, and permeability coefficients several orders of magnitude higher than those of top-layer samples at the same void ratio. In contrast, top-layer samples, which are predominantly fine-grained, display high compressibility, an inverted S-shaped compression curve, and low permeability; (2) Permeability is strongly influenced by both void ratio and fine-grained content: when the fine content exceeds 30%, a definitive correlation exists among permeability coefficient, void ratio at the liquid limit, and current void ratio; when fine content is 30% or less, permeability can be quantitatively related to the fine content and void ratio; (3) Under high initial water content conditions, bottom-layer samples develop a stable sandy skeleton that restrains compressive deformation and significantly improves permeability.

dredging mud;sorting effect;fine particle content;compressibility;permeability coefficient