Analytical solutions of 1‐D chemo‐hydro‐mechanical coupled model of saturated soil considering osmotic efficiency

Abstract

AbstractIn the complex chemical environment of municipal waste landfills, the chemo‐hydro‐mechanical coupled flows in the compacted clay layer (CCL) and its deformation are very complicated. When studying the chemo‐hydro‐mechanical consolidation of soil, the osmotic flow, ultrafiltration, and the osmosis effect on solute migration were neglected due to the low osmotic efficiency. However, the permeability of CCL of landfill is very small, and their osmotic efficiency is higher. The osmotic phenomenon and influence of osmotic efficiency must be considered. In this paper, a 1‐D chemo‐hydro‐mechanical coupled model of saturated soil is proposed considering osmotic efficiency. The analytical solutions of the model under specific boundary conditions were obtained by Fourier transform. The degradation model is compared with the existing governing equations and results in the literature, and the correctness of the proposed governing equations and analytical solutions is verified. Through the analysis of specific case, it can be concluded that chemo‐osmotic consolidation significantly affects the consolidation of the soil layers. The osmotic consolidation leads to the generation of negative pore pressure, but it decreases with the decrease of the osmotic pressure gradient. This process leads to the rebound effect of the soil settlement. The osmotic efficiency significantly affects the consolidation characteristics of this soil layer, and therefore the effect of osmotic efficiency must be considered in soils with high osmotic efficiency.