Temperature distribution analysis of high-speed railway roadbed in seasonally frozen regions based on empirical model

To study the roadbed temperature distribution rules in seasonally frozen regions, an empirical model based on three years' field monitored temperature data is proposed, which takes several important factors into account, i.e., the variation of average temperature, amplitude, phase difference, and soil properties along with time and space. To validate the proposed model, the roadbed temperatures with time at various depths, the frost depth value and its arrival date between the model and field monitored are compared and good agreement is obtained. Furthermore, based on the empirical model, the spatial and temporal temperature distributions of roadbed, such as frost penetration development, transverse temperature difference, freezing conditions, are detailed. The analyses indicate that the roadbed temperature distribution is mainly affected by geographical location as well as roadbed height, and the transverse temperature differences are widespread. The proposed model allows a more accurate analysis of roadbed temperature distributions in frozen ground regions and, thus, is more conveniently conductive for theoretical and laboratory research.