Abstract:A system of radial consolidation combined plastic wick drain and vacuum preloading is one of the most popular methods of soft ground improvement, which not only can reduce the height of surcharge preloading on dam, but also can reduce the lateral displacement of soil. The consolidation solution of plastic wick drains and vacuum preloading using nonlinear relationships of this paper can be greatly applied to forecast and analysis this kind of ground improvement. In the process of analytical solution, the relationship between void ratio and mean effective stress, horizontal permeability coefficient under one-dimensional consolidation is considered to be semi logarithmic linear, rather than previously thought one-dimensional linear. Because of disturbing on soil around PVD in smear zone, permeability around PVD in smear zone is distributed in parabolic form. Besides, the effect of vacuum preloading on consolidation is considered. Correctness of this analytical solution is verified through degradation method and compared with test results. Finally, the effects of , Ck/Cc, are analyzed on consolidation. The results indicate that consolidation rate increases with the increasing of Ck/Cc and decreasing of .