单线隧道缓冲结构参数的优化

Optimization of Structural Parameters of the Single-Line Tunnel Entrance Hood

摘要: 在隧道入口处修建缓冲结构，可以减缓高速列车进入隧道时产生的入口效应。为了优化单线隧道缓冲结构参数，本文采用计算流体力学三维动态仿真计算的方法，分析了单线隧道缓冲结构的长度、截面积、开孔率对隧道内初始压缩波的最大压力值和最大压力梯度值的影响，得到三个因素综合影响时的最优结构参数。结果表明：缓冲结构的长度、截面积、开孔率对压缩波的交互影响十分明显，且长度为80 m，截面积为120 m²，开孔率为40%时，最大压力梯度值能得到有效降低；在本文研究范围内，缓冲结构长度为80 m，截面积为140 m²，开孔率为20%时，可以有效缓解最大正压值。

Abstract: The hood, built on high-speed railway tunnel entrance, can reduce pressure pulse effects pro-duced by the train running into tunnels. In order to optimize structural parameters of a single-line tunnel entrance hood, the method of three-dimensional computational fluid dynamics was used to analyze the effects of the length, the sectional area and the opening ratio of an entrance hood on the maximum pressure and the maximum pressure gradient of the initial compression wave in the tunnel. The optimal structural parameters are obtained when the three factors are combined. The results show that the interaction between the length, the sectional area, and the opening area ratio of entrance hood is obvious. The maximum pressure gradient can be reduced effectively when the length is 80 m, the sectional area is 120 m² and the opening ratio is 40%. Based on this study, the entrance hood with the length of 80 m, the sectional area of 140 m² and the opening ratio of 20% can effectively reduce the maximum pressure.