3D Transport of Solute in Deformable Soils with Different Adsorption Modes

Abstract

Additional loading due to the weight of the waste in landfills results in consolidation and deformation of clay liners beneath, which will induce changes in the inner structure and permeability of the clay liners. Based on combination of Biot consolidation theory and solute transport theory, a three-dimensional coupled model describing solute transport in deforming soil has been proposed, taking account of the effect of consolidation on solute transport processes. The consolidation and transport equations are linked by choosing the permeability coefficients as the coupled parameter. The effects of different adsorption modes on solute transport processes in deforming soil under two conditions are studied: the solute source concentration remains constant or degrades with time. The solute concentration versus space with degraded-concentration source increases gradually and reaches a peak value at a certain depth in the vertical section or at a certain position in the horizontal section, and then decreases, which is very different from that with the constant-concentration source.