Large-strain consolidation of PVD-improved soils considering depth-dependent initial void ratio and initial effective stress due to soil self-weight

A governing equation for large-strain consolidation of PVD-improved soil is developed based on the equivalent elliptical cylindrical model, which accounts for depth-dependent initial void ratio and initial effective stress induced by soil self-weight, well resistance with variable discharge capacity, time-dependent load, and nonlinear variations of compressibility and permeability. Then, a numerical solution is obtained by means of COMSOL Multiphysics and is validated through comparisons with existing solutions and measured data. The parametric studies show that the difference between large-strain consolidation and small-strain consolidation reduces with the decreases of the compression index and applied load. Although the soil self-weight has little effect on the degree of consolidation in some cases, the soil settlement will be significantly overestimated if the self-weight is ignored. The development of consolidation slowed as the ratio of compressibility over horizontal permeability increased.