Thermo-Hydro-Mechanical Coupling Model of Unsaturated Soil Based on Modified VG Model and Numerical Analysis

A modified VG model considering both pore ratio and temperature effect is constructed. Based on the wet-thermal elasticity theory mixture theory, coupled thermo-hydro-mechanical (THM) equations for moisture migration, heat transfer, deformation in unsaturated soil are derived. The numerical implementation of was implemented by secondary development finite element platform. validity established theoretical equation verified comparing it with experimental data. Then THM coupling response characteristics internal mechanism axisymmetric samples were numerically analyzed. Study shows that water migrates from high-temperature zone to low-temperature under load, permeability will change during process absorption dehydration. Particular attention should pay reasonable determination parameters warming cooling different measurement points calculation. higher source temperature, greater saturation at specific point sample thermal stability. lower shorter time required stabilize measuring point. volumetric strain results a combination wet expansion expansion, which dominated near mainly far source. total displacement z -direction displacement, its trend along radial direction similar r -direction. peak curve keeps moving backward time.