A Mass-Conservative Numerical Solution for Finite-Strain Consolidation during Continuous Soil Deposition

Consolidation of accreting soft soils is a topic of significant interest for engineers dealing with mine tailings deposition, hydraulic fills, dredging deposits, and wetland construction. In these cases, the classical Terzaghi’s theory often fails to produce satisfactory solutions due to variations in compressibility and permeability under large deformations. The finite-strain theory introduced by Gibson allows for the non-linearity of material properties and provides an accurate description of soft soil deposits undergoing large displacements. Numerical accretion models based on Gibson’s theory need to account for both the non-linearity of the governing equation and the continuous domain change. This paper investigates the numerical performance of several one-dimensional finite-difference schemes with different time-stepping algorithms and mesh discretization procedures. An optimal mass-conservative scheme is selected and implemented into a numerical model. The presented field example demonstrates that the employed mapping technique ensures both mass and water conservation, essential for water balance and storage capacity prediction in slurry disposal projects.