Stochastic Moisture-Heat Coupled Processes of an Embankment in Permafrost Regions

Moisture-heat processes are important for the service performance of embankments in permafrost regions. The external boundary conditions and soil-water parameters involved in the moisture-heat processes are spatially and temporally uncertain due to complex and variable geological processes, stochastic climate conditions, human activities, and construction disturbances. In addition, the soil-heat parameters obtained through experiments have testing errors, leading to uncertainties. The associated uncertainties inevitably affect the moisture-heat processes of embankments, and the exact mechanism of those processes remains unclear. To explore the stochastic moisture-heat processes of the embankments, a numerical stochastic moisture-heat coupled model was first established. The simulation results show that the stochastic moisture-heat processes of the embankment exhibit seasonal differences. The stochastic fluctuation of temperature on September 15 was found to be the highest during a one-year period, while the stochastic fluctuations of the unfrozen water content and ice content were highest on January 15. We also found that the SDs of moisture-heat processes showed the largest fluctuations at the middle and bottom of the embankment. The findings of this study would serve as a reference to parameters selection of simulation and design, mechanism analyses of freezing-thawing damage and engineering reliability in cold regions