青藏铁路冻土沼泽化斜坡湿地路基稳定性研究

Study of the Stability of the Roadbed on the Inclined Slope of the Permafrost Swamp Along the Qing-Tibet Railway

结合青藏铁路安多段冻土路基的设计与施工,从地基斜坡、地基强度、地表水和温度场四方面分析了影响沼泽化斜坡湿地冻土路基稳定性的因素,提出了设计和施工过程中需要采取的保证路基稳定性的技术措施,例如在路基下部设置1m厚的片石层、路基体内设置双向土工格栅、在路基上游设置隔水板和挡水堤等;在此基础上对安多段沼泽化斜坡湿地冻土路基的水平位移进行了长期监测,监测表明路基稳定,为类似工程的设计和施工提供了参考依据。

With the design and construction of the permafrost roadbed in the Anduo District of the QinghaiTibet Railway as practical examples, the influential stabilizing factors of the roadbed on the inclined slope in the permafrost swamp are analyzed in the paper from the four angles of the inclined slope of the roadbed, the strength of the roadbed, surface water, and the temperature field, with effective technical measures of construction presented, which have to be taken to ensure the stability of the roadbed in permafrost swamp. Those technical measures include the provision of a one-meter rugstone layer below the roadbed, the provision of dual engineering grids inside the roadbed body, the provision of waterproof plates and waterblocking dams in the upstream section of the roadbed. On the basis of the above-mentioned measures, we also monitor,on a long-term in-situ basis, the lateral displacement of the roadbed. Our monitored results show that the roadbed has kept stable. The technical measures may serve as a useful reference for other similar projects.