A Novel Numerical Model for Coupled Large‐Strain Consolidation and Solute Transport in Clayey Soils Considering Chemico‐Osmotic and Creep Deformation
Peng‐Lin Li, Ding‐Bao Song, Zhen‐Yu Yin, Jian‐Hua Yin
Abstract
ABSTRACT Contaminated geomaterials in CDFs (confined disposal facilities) and CCLs (compacted clay layers) typically undergo a long‐term process involving coupled finite strain consolidation and solute transport, posing challenges for fully coupled modeling. To fill this research gap, a novel finite strain consolidation‐solute transport model incorporating chemico‐osmotic and creep effects is developed. The predictive accuracy of the model is verified through comparisons with existing analytical and numerical solute transport models with consolidation effect, a finite‐strain consolidation model, and a small‐strain HMC (hydro‐mechanical‐chemo) model. The model effectively replicates oedometer tests with one‐step and three‐step salinization, revealing significant volume changes (15.6% and 5.74% for two tests) due to chemical loading, even larger than those (5.31% and 5.13%) due to mechanical loading. Finally, parametric studies highlight the influence of creep, compressibility, boundary conditions, initial concentration distribution, and adsorption, demonstrating that chemico‐osmotic effects can generate large negative pore pressures (50% of initial pore pressure) and average consolidation degree (about 140%). Compared with consolidation‐related parameters, the adsorption coefficient has a more noticeable effect on solute transport, leading to bottom concentration values ranging from 54% to 25% of the boundary concentration value as the adsorption coefficient increases from 0 to 1.5 mL/g. Overall, consolidation exhibits greater sensitivity to parameter variations than solute transport in these cases.