Thermo-mechanical behavior and thermal regulation measures of subgrade layer in roads under stochastic periodic thermal disturbance
摘要
The characteristics of frost damage of highways under hydrothermal conditions are driven by large temperature differences, high soil moisture content, and disparities in both the temporal and spatial distribution of snow depth. The ground surface temperature (GST) model, which characterizes random dynamic variations in snow depth, was coupled with a thermal-hydro-mechanical model of frozen soil. Utilizing the coupled model, variations in GST and heat flux across six snow depth scenarios were computed, along with the evolution of the subgrade temperature field and pavement deformation. Furthermore, the response of the thermal state of the ground surface and the thermal behavior of the subgrade to fluctuations in four snow depth ranges were systematically examined, and the influence mechanism of snow on the subgrade thermal stability was revealed. In view of the preceding analysis, a comparison and evaluation were made of the regulatory effects of conventional and improved thermal regulation measures on the deformation characteristics of the subgrade top surface, under conditions of two extreme snow depths and four snow depth fluctuation ranges. This study provides direct guidance for the control of frost damage in snow-covered permafrost subgrades subjected to stochastic periodic thermal disturbances.