Nonisothermal Consolidation in Unsaturated Soil

Abstract

Consolidation of unsaturated soil depends upon changes in stress‐state variables resulting from applied stress and movement of pore water and gas. Water movement is highly dependent on heat flow, and much water movement takes place in the vapor phase. Consequently, water movement, soil deformation, and heat flow in an unsaturated soil mass are coupled phenomena. Equations are developed to describe water movement and deformation as functions of time, taking into account evaporation and temperature effects. In these equations, coordinate transforms are defined that‐allow finite strain conditions to be included. A computer model was developed to solve these equations. Good correlation was observed between the model and results for standard cases of rigid, partially saturated flow and saturated consolidation. Examples are presented for drainage of singleand multiple‐layered soil. An example is also presented for a uranium mill tailings profile comprising several layers with placement of a cover on the surface and taking into account both drainage and evaporation.