Terzaghi’s one-dimensional consolidation theory is modified based on the non-Darcy seepage equation considering the initial hydraulic gradient

and the finite difference scheme is introduced. The effects of the initial hydraulic gradient on the seepage front

the pore water pressure and the degree of consolidation are thereby investigated. The analytical results indicate that

for the soil with the initial hydraulic gradient greater than zero

the hysteretic appearance of seepage flow in the soil layer apart from the drainage boundary makes the rate of consolidation less than that by applying Terzaghi’s consolidation theory. In addition

it is validated that the ultimate value of average degree of consolidation is less than 1 since there exists some residual pore pressure which cannot be completely dissipated in the soil layer.