青藏铁路风火山隧道气温轨温试验及无缝线路设计

Experiment of air and rail temperature and design of CWR track of Fenghuo mountain tunnel on Qinghai-Tibet railway

研发了适合青藏高原恶劣气候环境的气温轨温自动采集存储系统.首次对青藏铁路风火山隧道内外的气温和轨温进行了为期1年的连续测试,获得了其变化特点.在此基础上,进行了风火山隧道无缝线路锁定轨温设计.利用有限单元法建立了无缝线路轨道结构的有限元模型,分析了风火山隧道无缝线路采用长钢轨贯穿隧道布置方式的可行性,计算了轨温过渡区的钢轨温度力梯度和最大钢轨伸缩位移.计算结果表明:当轨温过渡区长度为30-50m时,风火山隧道无缝线路可采用该种轨条布置方式,但需要布置一定数量的防爬设备.

An automatic acquisition and storage system of air and rail temperature suitable for the harsh climate environment on Qinghai-Tibet Plateau was developed. A one-year continuous measurement of the air and rail temperature in and out of Fenghuo mountain tunnel on Qinghai-Tibet railway had been carried out for the first time. The change regularity of the air and rail temperature inside and outside Fenghuo mountain runnel was obtained. According to the change regularity, the design of fastening down temperature of continuously welded rail （CWR） track for Fenghuo mountain tunnel was finished. The model of CWR track was established by finite element method to study the feasibility of the layout of long rail strings crossing the tunnel. The rail temperature stress and telescopic displacement of CWR track in the rail temperature transition zone near the tunnel entrance were calculated. The results show that the layout of long rail strings crossing the tunnel can be adopted when the length of rail temperature transition zone is around 30-50 m, hut a certain number of anticreepers must be laid on the transition zone.