Abstract: The dredged soil has the engineering properties of high moisture content, high compressibility, low shear strength and low permeability. With a nonlinear characteristic, the consolidation process of the dredged soil is different from the conventional soft soils. This paper presents the results of consolidation tests on two types of dredged ultra-soft samples. The following conclusions can be obtained: 1) Under the first loading increment, the highest compression (highest compression coefficient) was observed in both types of samples.  Lower compression coefficient was found in higher consolidation load. A linear relationship between the void ration and the logarithmic consolidation pressure. 2) The coefficient of consolidation in both types of soil samples increased and the coefficient of permeability decreased with the increase of the consolidation pressure. 3) nonlinear relationship can be found between the logarithmic coefficient of permeability and the void ratio and this relationship (log kve) could be established by using a nonlinear curve fitting.

Key words: Ultra-Soft soils, compression, consolidation, seepage