Study on the effect of step ratio to temperature field of cut-fill transition in deep seasonal frozen soil region

Abstract

The existing studies lack numerical simulation of the temperature field in the cut-fill transition of the deep seasonal frozen soil regions. The ratio effect of steps in the backfill area of cut-fill transitions has also been little studied. Therefore, this paper establishes a numerical model based on some geological and meteorological data of Yichun City, China. It simulates the temperature field process of the cut-fill transition for the next 10 years under three ratio step conditions: 1:1, 2:3, and 1:2. The results show that the temperature field of the subgrade corresponding to different working conditions varies relatively significantly in terms of maximum freezing depth and frozen layer morphology. The law shows that in the cut-fill transition section, the gentler the step gradient is, the deeper the maximum freezing depth is, and the larger the frozen layer retained area in the thaw period. The retention of frozen interlayers is likely to cause differences in subgrade stiffness and exacerbate the “thaw-basin” phenomenon. Therefore, this study recommends 1:1 ratio of steps as the optimal program for the construction of backfill area, and can be targeted according to the numerical results of this paper in the arrangement of drainage, insulation and other measures.