Influence of hydration heat on stochastic thermal regime of frozen soil foundation considering spatial variability of thermal parameters

Construction method of cast-in-situ concrete is very popular for the foundation engineering in permafrost regions. But the hydration heat of concrete can lead to the melt of ice in frozen soil zone, and then the temperature variation can lower the bearing capacity of frozen soil foundation. In this study, a three-dimensional (3D) stochastic thermal model of frozen soil foundation with phase change and internal heat source is proposed, and the influences of the hydration heat on the stochastic thermal regime of frozen soil foundation are estimated. Considering the different variability of thermal conductivity, heat capacity and latent heat, a sensitivity analysis for the stochastic thermal regime is presented. The results show that the hydration heat of concrete has a great influence on the stochastic thermal regime of frozen soil foundation in the early days after the base constructed. The variability of temperature is more obvious when the distance from the footing centerline is close. Different variability of the thermal parameters has a different effect on the stochastic thermal regime. These results can improve our understanding of the influences of hydration heat on the stochastic thermal regime and provide a theoretical basis for the safety of cast-in-place construction method.