Thermo-hydro-mechanical behaviour of partially saturated fine-grained soils in the context of energy geostructures

The multi-physical phenomena, particularly water content and temperature variations, governing the behaviour of soils should be considered in the design and analysis of the energy geostructures. Soil temperature and water content variations impose a significant risk on the stability and serviceability of existing and future geostructures. Although potential failure modes, impacts at a system scale, and the response of saturated soils to thermal loads are previously discussed, interpretation of the thermo-hydro-mechanical behaviour of partially saturated soils in the context of energy geostructures is not thoroughly investigated. In this regard, this paper brings together the experimental data from several laboratory investigations to attain a comprehensive understanding of the partially saturated fine-grained soils response under thermo-hydro-mechanical loading, which plays a vital role in the analysis of the soil behaviour and energy geostructures in contact with them. In this paper, the effect of thermal loading in different matric suctions and hydraulic loading at different temperatures on soil preconsolidation stress, water content variation, thermal and hydraulic conductivities, and compression indexes are studied. Furthermore, soil thermal deformation is studied in detail for different overconsolidation ratios and matric suctions.