Analytical Solutions for One-Dimensional Large-Strain Nonlinear Consolidation of Soft Soils by Considering a Time-Dependent Drainage Boundary

Abstract

Over the past decades, many advances have occurred for theories on large-strain nonlinear consolidation of soft soils with regard to traditional drainage boundaries, which are completely permeable and impermeable cases and which may not truly reflect the whole process of drainage boundary. Thus, some further considerations related to a time-dependent drainage boundary are adopted in the analysis of soft soil consolidation by incorporating biologarithmic compressibility and permeability models. Also, the analytical solutions are obtained by means of variable substitution and Laplace transform. Additionally, the proposed solution is degenerated and compared with the existing solution and the laboratory tests to validate its correctness and feasibility. Finally, the soil consolidation behavior is analyzed under different values of the interface parameter, nonlinear compressibility and permeability, and external loading. The results indicate that the drainage boundary permeability is largely determined by the interface parameter; the larger the interface parameter, the better the boundary permeability. Besides, the consolidation rate decreases with the increasing value of Ic(α − 2) when the external loading remains constant. While the parameter Ic(α − 2) is a constant value, the consolidation rate varies with the external loading. Therefore, appropriate parameter values are more conducive to the full consolidation of soft soil foundations.