ABSTRACT
Several geotechnical applications such as nuclear waste disposal storage, buried high-voltage cables, pavements and geothermal energy are subjected to non-isothermal loading stages. The prediction of their behaviour requires constitutive models able to reproduce its response under a wide range of loading and thermal conditions. This paper is devoted to the development of a coupled thermo-hydro-mechanical hypoplastic model for fine-grained soils with the consideration of small-strain effects. Its formulation is based on the coupled-hydro-mechanical hypoplastic model by Wong and Mašín (2014) extended to account for temperature effects. The resulting constitutive model predicts large strain asymptotic behaviour and small-strain path-dependent effects on unsaturated conditions at different temperatures. Selected simulations were carried out to validate the proposed model based on the experimental results of constant water cyclic triaxial tests under suction- and temperature-controlled conditions, performed by Ng and Zhou (2014) on a completely decomposed tuff subjected to constant water cyclic triaxial loading at suction and temperature-controlled conditions. The comparison between experimental and simulation results suggests that the proposed constitutive model accurately reproduces the influence of temperature on the accumulation rates of strain under cyclic loading at partially saturated conditions.
