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| Experimental Research on the Stability of Embankment-bridge Transition Section of High-speed Railway in Seasonal Frozen Regions |
| SHEN Yu-peng1, DA Zhi-hua1, YUE Zu-run2, TIAN Ya-hu1 |
| (1. Beijing Jiaotong University, Beijing 100044, China; 2. Shijiazhuang Tiedao University, Shijiazhuang，Hebei 050043, China) |
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Abstract Abstract：Research purposes： For the high-speed railway lines with more embankment-bridge transition section, the control of the deformation difference between the road and bridge transition section is an important factor to ensure the smooth operation of the train, especially in deep seasonal frozen regions. In this paper, a transitional section of Harbin-Qiqihar Railway is used as a pilot monitoring section, based on the field test data of ground temperature change, frost deformation and settlement deformation, the ground temperature change, frost deformation of subgrade surface and settlement of subgrade basement of embankment-bridge transition section of high speed railway in cold regions are analyzed, the ground temperature and deformation characteristics are revealed, thus the stability of embankment-bridge transition section can be evaluated. Research conclusions： (1) At the initial stage of construction, graded crushed stone is easier to be endothermic and exothermic compared to coarse grained soil as for backfill materials of bridge back; the temperature difference in corresponding depth of these two kinds of fillers decreases gradually and tends to 0℃, and finally the new thermodynamic equilibrium is formed. (2) During the freezing process, the maximum deformation of embankment-bridge transition section is 4.6 mm, meeting the requirements of specification. (3) Graded crushed stone being adopted as backfill materials of bridge back, the change process of frost heave deformation of subgrade surface layer with the temporal and spatial can be divided into four stages: the rapid development period of frost heave, frost heave relatively stable period, frost uplifting stage and thaw felling period. (4) The relationship between frozen depth and frost heave deformation of surface layer of embankment-bridge transition section is nonlinear when graded crushed stone is applied. But, the maximum frozen depth of embankment influences the maximum cumulative frost heaving value of the subgrade surface. (5) The settlement of the southern slope is greater than the northern slope. The closer to the northern slope-toe, the settlement and deformation amplitude of substrate becomes smaller. During the period between completion of subgrade construction and track laying, the settlement of basement increases slowly. Currently, the settlement deformation amount of each measuring points of the basement meets the standard requirements. (6) The research results can further provide reference for engineering design, construction and maintenance in the future.
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Received: 25 October 2017
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2018, Vol. 35 
