Variation in Subgrade Temperature of Highway in Seasonal Frozen Soil Region

摘要

Abstract Freeze–thaw cycles in seasonal permafrost areas are a dominant cause of road damage. Therefore, the roadbed fill must be frost-resistant. In this study, taking the experimental section of the asphalt concrete pavement structure of the Zhangcheng Expressway in the seasonally frozen soil area of Hebei Province as an example, three working conditions were selected: a low embankment with a waterproof geotextile partition layer, a low embankment with a gravel layer + extruded polystyrene (XPS) board, a high embankment with a gravel layer + two pieces of cloth, and a waterproof geomembrane. After 2 years of tracking and analysis of the measured data, the subgrade temperature distribution law was derived in terms of time and depth to obtain the freezing depth under each working condition. The experimental results showed that the gravel bedding layer, XPS plate, and geosynthetic materials had a significant effect on the prevention and mitigation of road disease, and therefore, their application must be promoted.