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青藏铁路站场路基比一般铁路路基宽度大,为此,在清水河高温细粒土地段进行了专门的现场试验研究。通过采用不同深度处地温场变化、上限变化、阴阳坡温度变化以及积温等分析方法,对该试验段3个冻融循环过程中监测到的温度场分析,并与普通路基的温度场数据进行对比。通过分析可以看出,站场路基下人为上限的上升幅度比普通路堤要大,路基表面以下同样深度处的地温,站场路基下的地温要低于普通路堤下的地温,因此路堤宽度较大的站场路基对多年冻土的保温效果比普通宽度的路堤好。由变形观测数据看出,冻胀量较小,变形主要为沉降变形,路堤阳坡冻胀板的变形量要大于路堤阴坡相应位置的冻胀板变形量。阳坡上层冻胀板最大沉降量是0.241 m;下层冻胀板最大沉降量0.237 m,且随着时间推移,变形趋于稳定。
Qinghai-Tibet Railway Station roadbed than the general railway embankment width, therefore, in the Qingshui River high-temperature fine-grained soil section of a dedicated field trial study. Through the analysis of the change of temperature field, the upper limit, the temperature change of yin-yang slope and accumulated temperature at different depths, the temperature field monitored during the three freeze-thaw cycles in the experimental section was compared with the temperature field data of normal subgrade . It can be seen from the analysis that the increase of man-made upper limit under the subgrade of station yard is larger than that of ordinary embankment, the ground temperature under the same depth below the subgrade surface and the ground temperature under subgrade of station yard are lower than the ground temperature under common embankment, Of the station subgrade to the permafrost insulation effect than the average width of the embankment is good. According to the deformation observation data, the amount of frost heaving is small and the deformation is mainly settlement deformation. The deformation of the frost heave plate on the embankment sunny slope is greater than the deformation of the frost heave plate corresponding to the shady slope on the embankment. The maximum settlement of the frost heave plate on the sunny slope is 0.241 m. The maximum settlement of the frost heave plate at the lower layer is 0.237 m, and the deformation tends to be stable with the passage of time.