青藏铁路桥头路基变形分析及治理方案

Analysis and controlling method of deformation in bridgehead roadbed of Qinghai-Tibet Railway

对青藏铁路多年冻土区某一桥头路基沉降变形及地温数据进行分析,总结出引起该桥头路基下沉的主控因素为:1热侵蚀,热侵蚀致使其下伏冻土融化,是引起桥头路基下沉的一个主要因素;2太阳辐射,路基两侧边坡表面吸收的太阳辐射能的差异影响着坡面热状况差异,进而影响到了路基横向的热差异,导致不平衡的冻融状态,产生不均匀沉降。提出了相应的治理措施,为同类地区桥头路基沉降的治理提供参考。

Through the analysis of the bridge subgrade settlement deformation and the temperature data in permafrost region of Qinghai-Tibet railway. The paper extractes the main control factors of the bridgehead roadbed subsidence： （1）Thermal erosion： Thermal erosion cause the underlying permafrost melts, is a major factor in causing sinking of the bridgehead subgrade. （2） Solar radiation： the difference of solar radiation amount on both sides of the subgrade slope results in transverse thermal difference, and lead to the freeze-thaw imbalance, at last, it will cause uneven settlement. Author puts forward corresponding control measures. Author hopes that this paper can provide reference for the governance of subgrade settlement in permafrost regions .