从河床冲淤分析沉管法修建长江水下隧道问题

文章从三峡水库泥沙入库量的减少以及三峡水库对泥沙的拦截作用两个方面分析了三峡水库对长江中下游河床冲刷的影响,具体剖析了现有冲刷数值模拟的最大冲刷量远较实际冲刷量为小的原因,因此得出了在三峡以下长江中下游不宜采用沉管法修建长江水下隧道的结论。对于重庆地区朝天门两江隧道的修建方案问题,文章在分析了决定修建沉管隧道方案可行性的两个关键参数,即河床水深和水流流速后,指出只要采取相应工程措施,采用沉管法修建两江隧道是可行的。

On building immersed tube tunnel under Yangtze River from the analyses of riverbed scour and siltation

Based on analyzing the reduction of silt into Three Gorges reservoir and the riverbed scour by the influence of Three Gorges reservoir,the paper points out that the maximum scour amount is much greater than the current scour amount determined by numerical simulations up to date.For this reason all analyses bring to the conclusion that the immersed tunnel project is not acceptable in the middle and lower reaches of Yangtze River.For the construction scheme of Liangjiang tunnel in the area of Chaotianmen of Chongqing,two key parameters deciding the feasibility of immersed tunnel project,i.e.water depth of riverbed and velocity of water flow,are analyzed.The analysis result brings to the conclusion that the immersed tunnel scheme of construction is feasible after adopting some engineering measures.