Controls on freezing-thaw cycles in a fully coupled thermo-hydro-mechanical system in permafrost area, Central Mackenzie Valley, Northwest Territories

This study will collect a series of temperature and moisture observations from existing column experiments to verify the development of coupled moisture and heat transport model. Other selected analytical and numerical results will also be compared with our simulations. In addition, the typical strain and/or stress measurements from available literature will be used to validate the coupled THM model system. In the one dimensional and two dimensional synthetic case models, simulations will produce high-resolution of temperature, thermal conductivity, heat capacity, liquid water, ice water, freezing point depression, saturation degrees, hydraulic conductivity, stress, strain, frost penetration, deformation rate, potential damage-crack, etc., in space and time. While in the virtual and real watershed cases, the collected long-term time series of field observations, such as hydrogeological maps, hydraulic head, fluxes, precipitation, temperature, ground surface subsidence, chloride concentration, and so on, will be used to calibrate and validate the model.

Numerical analysis of coupled water, vapor, heat, and stress fields are used to quantify the interactions between surface water and groundwater flow and thermal dynamics related to freezing-thaw and expansion-settlement in seasonally frozen areas. The model structure will be calibrated and validated using measurements, such as the moisture, temperature, and strains in the literature. Then, a virtual watershed approach will be used to test and modify the coupled framework, according to field observations and other well-recognized scientific findings. Finally, this modified model framework will be applied into typical permafrost area, to investigate thermo-hydraulic-mechanical (THM) dynamics, and predict possible damage-related processes in the context of climate change. This model framework and generated data will support the project titled “North Water Futures Big Data Platform and "Smart Watersheds". These are Pillar 3 project under the Global Water Futures Program funded by Canada First Research Excellence Fund.

Rudolph, D., and Huang, X. (2019). Controls on freezing-thaw cycles in a fully coupled thermo-hydro-mechanical system in permafrost area, Central Mackenzie Valley, Northwest Territories. Canadian Cryospheric Information Network (CCIN). Unpublished data.

Bogg Creek Watershed, Central Mackenzie Valley, Northwest Territories