Frost Damage Improvement for Railway Subgrade Based on Ground Temperature Control in Cold Regions

Due to the ignorance of the influence of frozen soil during the design period, the frost damage of subgrade in Datong-Junggar Railway was serious. The improvement scheme of frost damage was researched. However, the research based on the existing project was few, and previous improvement schemes could have an impact on the normal operation of railway system. Datong-Junggar Railway has undertaken the important task of transporting coal resources for China since its normal operation. To ensure normal operation of existing railway, the heating hole scheme was investigated by finite element simulations. The embedding spacing, the heating hole temperature and the embedding depth were analyzed. Based on the simulated results and on-site conditions, the design scheme of the heating hole (embedding spacing: 1.0 m, the heating hole temperature: 30°C and embedding depth: 70 cm) was proposed. Finally, the on-site monitoring in Qianshimen was taken to verify the feasibility of the heating hole scheme. Under the continuous energizing condition, the ground temperature remained basically stable even though the temperature had dropped to −7°C. The research results could enrich the design schemes for frost damage in cold regions from the aspect of ground temperature control.