Characteristics of road freezing-thawing environments in China oriented towards construction and maintenance

Abstract Road infrastructure suffers irreversible damage during service due to periodic or seasonal freeze-thaw (F-T) cycles, resulting in significant economic losses to the nation. However, systematic evaluation parameters for the entire road F-T environment are lacking, and there is insufficient understanding and short-term prediction of the underlying F-T environment changes and distribution. In this study, 13 F-T environmental parameters in three categories were summarized by combining meteorological parameters and multi-field evaluation parameters. Taking Shiquan River Town as an example, the statistical probability of road F-T environmental parameters was clarified by using the generalized extreme value (GEV) distribution. The study also clarified the spatiotemporal characteristics of road F-T environment across regions based on key F-T environmental parameters. The frequency of F-T events in China increases from south to north and from east to west, and F-T processes are influenced by regional altitude and latitude. Meanwhile, the temporal variation of the F-T environment in China shows significant seasonality. The F-T environment transitions from short-duration, high-frequency F-T cycles to longer-duration, low-frequency F-T cycles. The initial moisture condition of the road F-T environment in the northeastern regions increases, but the additional moisture during the F-T process decreases. This study provides critical insights into understanding the underlying mechanisms and short-term prediction of the road F-T environment changes, which can be used as a basis for the planning, construction, and maintenance of road infrastructure in China.