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Résumé :
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Temperature changes and deformations were monitored on various embankment types on the Qinghai-Tibet Railway. Some of these embankments utilized permafrost protection techniques such as duct ventilation, crushed-rock embankments, crushed-rock protected slopes, or thermal-insulation treatments. Some embankments were built conventionally without considering permafrost protection. It was found that the majority of the deformations on both the permafrost-protected and the conventionally built embankments were due to deformation of warm frozen layers closely related to the temperature changes in the underlying permafrost. However, it was found that building embankments with permafrost protection reduced the magnitude of the settlements. After 2–3years , deformation of all the embankments with permafrost protection countermeasures became smaller and smaller, whereas deformation was still increasing in the conventional embankments, where the settlement in the underlying permafrost could reach a considerable level, and could be a potential trigger for embankment failure. This should be taken into consideration in the railway engineering project on the Qinghai-Tibet Plateau.
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