Thermo-hydro-mechanical analysis of frost heave of unsaturated soils

Freezing and thawing of soils can cause volume change and result in potential damage to foundations and infrastructures. Modelling the dynamics of the phase change front between frozen and unfrozen soil regions as well as the interface between saturated and unsaturated soils involves accommodating strong nonlinearities and discontinuities in the physical fields of the problem. In this paper, the development of a coupled thermo-hydro-mechanical model for predicting the soil freezing and thawing behaviour is presented that is based on the non-local peridynamics theory. The model is tested via a series of verification and validation exercises against numerical and experimental benchmarks. In this paper, we show that bond-based peridynamics model successfully reproduced the results of a one-dimensional laboratory test of soil freezing for both open and closed water flow conditions. The performed calculations enable the analysis of the model parameters on the prediction of frost heave. The paper results confirm that the developed non-local approach can be used to predict heat and water transfer with associated soil volume expansion during freezing and thawing and be a key tool for ground-freezing engineering design. • A new bond-based Peridynamic (PD) model of THM soil behaviour is developed. • The expansion of soils during freezing is analysed. • Agreement between the developed PD solutions and experimental results is shown. • A PD approach for the description of unsaturated soil saturation is proposed.