In-situ study of permafrost embankments of Qinghai-Tibet Railway Station

Owing to the wider embankments of the station yard of Qinghai-Tibet Railway than the ordinary ones,a special in-situ test study was performed for the high temperature fine-grained permafrost section of Qingshuihe.By the variation of temperature fields at different depths of embankments,variation of frost table,temperature distribution of shaded side and sunny side and accumulated temperature,3 groupes of frost-thaw test data were analyzed and compared with those of general embankments.It was found that the rising amplitude of frost table of station embankments was larger than that of the ordinary embankments,and at the same depth,temperature of station embankments was lower than that of ordinary embankments.That is,station embankments were more effectively protected from permafrost than the ordinary embankments.From the data of deformation,swell deformation was small,the main deformation was settlement.The settlement of sunny side was larger than that of shaded side.In sunny side,deformation of the upper layer was 0.241 m,and that of the lower layer was 0.237 m,and with the in crease of time went on,the deformation came to stable.