No abstract

No abstract

Based on the non-Darcian flow law described by exponent m and threshold gradient i 1 under a low hydraulic gradient and the classical nonlinear relationships e-lgσ′ and e-lgk v (Mesri and Rokhsar, 1974), the governing equation of 1D nonlinear consolidation was modified by considering both uniform distribution of self-weight stress and linear increment of self-weight stress. The numerical solutions for the governing equation were derived by the finite difference method (FDM). Moreover, the solutions were verified by comparing the numerical results with those by analytical method under a specific case. Finally, consolidation behavior under different parameters was investigated, and the results show that the rate of 1D nonlinear consolidation will slow down when the non-Darcian flow law is considered. The consolidation rate with linear increment of self-weight stress is faster than that with uniform distribution one. Compared to Darcy's flow law, the influence of parameters describing non-linearity of soft soil on consolidation behavior with non-Darcian flow has no significant change.

Based on the axisymmetric consolidation model, the governing equation and the corresponding solution were developed for the consolidation of a composite foundation with an impervious column by incorporating an arbitrary stress increment. Then, the consolidation behavior was investigated as part of the parameter analysis for a composite foundation with an impervious column. The results show that the consolidation rate for a composite foundation with an impervious column was slower than that for a composite foundation with a granular column but was more rapid than that for a natural soil foundation. The consolidation rate accelerated with increasing values of the column-soil constrained modulus ratio or the top-to-bottom stress increment ratio and with decreasing values of the loading period or the radius ratio of the influence zone to the column. The column-soil total stress ratio increased with consolidation and approached the value of the column-soil constrained modulus ratio.