Thermo-poromechanical behavior of saturated silt clay: Experiments and constitutive modeling

This work aims to investigate the thermo-poromechanical behavior of saturated silt clay (SC) under varying temperatures through experiments and constitutive modeling. A series of undrained triaxial compression tests was conducted on saturated SC with temperature ranges from 25 °C to 60 °C. The effects of temperature on the main poromechanical properties of saturated SC, such as stress-strain relations, pore pressure evolution, and strength parameters, were thoroughly examined. Based on the experimental results, a subtly thermodynamically consistent thermo-poromechanical model was established using the concept of effective plastic stress within the poromechanical framework. Plastic deformation was described with a specific yield criterion and non-associated plastic potential that both depend on the effective plastic stress and a simple hardening variable. Finally, this model was implemented by a semi-implicit return mapping algorithm (SRM) and validated through the comparison of model predictions and experimental data. The proposed model accurately reproduces the main thermo-poromechanical characteristics observed in saturated SC.