高速铁路隧道空气动力效应对水沟盖板稳定性的影响研究

Study on Aerodynamic Influenceon on Stability of Ditch Covers in High-speed Railway Tunnels

采用数值模拟方法,对高速列车在隧道内运行过程中所产生压力变化过程和分布特性进行分析;计算列车运行过程中隧道内不同位置最大负压;探讨隧道内列车运行负压作用下水沟盖板稳定性计算方法;确定盖板不同漏气面积下密封指数;分析不同行车工况及不同漏气面积条件下水沟盖板稳定性。结果表明:隧道内水沟盖板承受正负交替压力,其中负压峰值较大,对水沟盖板稳定性影响显著。水沟盖板提升量随盖板顶面漏气面积减小而明显增大。当盖板漏气面积小于5cm2时,盖板稳定性不能得到保证。我国目前高速铁路隧道水沟盖板在350km/h会车工况下,盖板提升量不大于0.6mm,列车通过时盖板会出现响动。可适当增大隧道内水沟盖板手孔尺寸以减小这种响动。

The changing process and distribution of pressure produced by high-speed trains running through a tunnel were studied with the numerical simulation method. The maximum negative pressures at different positions in a tunnel were calculated. The method for calculating the stability of ditch covers under negative pressures was discussed. The seal indexes of the cover with different air leakage areas were determined. The stability of ditch covers with different air leakage areas under different train running conditions was analyzed. The calculated results show as follows： Positive and negative pressure act on ditch covers alternately, the negative peak pressure is great comparatively and affects the cover stability significantly; the upward displacement of the cover increases significantly with decreasing of the air leakage area of the cover; when the air leakage area of the cover is less than 5 cm, the stability of the cover cannot be guaranteed; under the condition of train crossing at 350 km/h in a tunnel in China, when the upward displacement of the cover is less than 0.6 mm, noises will appear; the size of the hand holes of the ditch covers may be increased appropriately to reduce the moving noises of the covers.