Radial Consolidation Solution of Plastic Wick Drain Combined Vacuum Preloading

A system of radial consolidation by combining the plastic wick drain with the vacuum preloading is one of the most popular way for soft ground improvement, which can not only reduce the height of surcharge preloading on dam, but also reduce the lateral displacement of soil. The consolidation solution of plastic wick drains and vacuum preloading based on the nonlinear relationship can well forecast and analyze this kind of ground improvement. In the process of analytical solution, the relationship between the void ratio and the mean effective stress, as well as the 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 the zone distributes in parabolic form. Besides, the effect of vacuum preloading on consolidation is taken into consideration. This analytical solution is verified through degradation method and compared with test results. Finally, the effects of κ, Ck /Cc are analyzed on consolidation. The results indicate that consolidation rate increases with the increasing of Ck /Cc and decreasing of κ