Warming performance of a novel high-speed railway embankment in seasonally frozen ground regions

In seasonally frozen ground regions, freeze-thaw (F-T) cycles induce frost heave and affect the long-term stability of high-speed railway embankments. This study used a molecular vibration infrared nano-thermoprobe (MVINT) to address frost heave by actively heating embankments. Both embankments, one with MVINT and the other without, underwent five F-T cycles in a refrigeration room. The temperatures, unfrozen water contents, and vertical deformations of the two embankments were monitored and compared for analyzing the frost heave mitigation effect of MVINT. After undergoing five F-T cycles, the proportion of negative temperature area in the embankment without MVINT reached 66.45%. In contrast, the embankment with MVINT exhibited significantly higher temperatures than its counterpart without MVINT. Its negative temperature area accounts for 4.61% and can only be observed at the slope toe. The results indicate that the heat provided by MVINT can significantly increase the overall temperature of the embankment. The unfrozen water content of the embankment without MVINT exhibits periodic fluctuations, whereas that of the embankment with MVINT gradually decreased and stabilized at 18.1%. Furthermore, the vertical deformations at the top surface of the embankment without MVINT are greater than those with MVINT. The maximum vertical deformation difference at the centerline of the two embankments is 1.07 mm, and the maximum vertical deformation difference at the shoulder is 0.67 mm. These demonstrate that the heat generated by MVINT effectively warms the embankment and reduces frozen depth. Therefore, MVINT is proved to be a reliable solution for mitigating frost heave in seasonally frozen ground regions.