高寒高海拔隧道进出口海拔差下列车内外压力计算方法及应用

Calculation Method and Application of Internal and External Pressure of Train in Tunnel with Elevation Difference at Entrance and Exit in Cold and High-altitude Area

为研究西部艰险山区长大隧道进出口存在较大海拔差下的车内外压力计算方法,采用理论分析方法对现有平原地区车内外压力单维计算模型进行修正,使之适用于进出口存在海拔差的隧道。通过青藏铁路列车内压力实测数据的对比,验证计算方法的正确性,并在实际设计中进行应用。主要结论如下:1)根据大气压力随海拔变化的规律,通过调整原有计算模型中每一时刻对应的基准压力、温度、密度和声速,可实现进出口存在海拔差隧道内列车内外压力的计算;2)通过此计算方法,确定了某高海拔山岭轨道交通单线隧道断面净空面积为19.5 m^2,双线隧道断面净空面积为41.5 m^2,列车动态密封指数最低要求为2.5 s。

The calculation method of the internal and external pressure of the vehicle passing through the long and large tunnels with the altitude difference between the tunnel entrance and exit in the western mountainous areas in China is of great significance.As a result,the theoretical analysis method is used to modify the single-dimensional calculation model of the internal and external pressure of the vehicle in the plain area to make it suitable for the tunnel with a difference in elevation between the entrance and exit.The feasibility of the calculation method is verified by comparing with the measured data in the train of the Qinghai-Tibet Railway,and the calculation method is applied to actual design.The main conclusions are drawn as follows:(1)According to the variation law of the atmospheric pressure with the altitude,the calculation of the internal and external pressure of a train in an altitude difference tunnel can be realized through adjusting the reference pressure,temperature,density and sound speed corresponding to each time in the original calculation model.(2)The calculation results show that the clearance area of the single-track tunnel of a high-altitude mountain rail transit is 19.5 m 2,that of the double-track tunnel is 41.5 m 2,and the minimum requirement of the dynamic sealing index of the train is 2.5 s.