严寒地区客运专线路基冻胀原因及处治措施

针对严寒地区客运专线路基段线路在冬季时出现的抬升情况，通过现场勘探、检测结果，线路抬升是因路基在冬季负温下基床内水的冻结膨胀所致。地表水下渗、地下水毛细作用和冻结过程中的聚冰效应致使基床含水率超过最优含水率一定范围时，即使是粗颗粒填料，在严寒低温下填料冻胀率随填料含水率增大而增大。根据以上原因，采用渗水盲沟等措施，确保了既有设施的安全。

Genesis and Treatment Measures on Frost Heaving of Subgrade for PDL in Severe Cold Area

In relation to track lifting of PDL in winter in severe cold area, it is inspected through field exploration to be caused by frost heaving of water inside the subgrade bed under subzero temperature in winter. As a result of ice assembling effect during surface water permeation and underground water capillary action and frost, the water content inside the subgrade bed exceeds the optimal water content to an extent that even if coarse-grained filler is used, the rate of frost heaving of the filler at extremely low temperature increases with the increase of the water content of the filler. Therefore, permeable blind ditch is used to ensure safety of the existing facilities.