Abstract:Research purposes:The terrain and geological conditions of the southwest mountainous areas are complicated. It is inevitable that tunnel of high - speed railway has to under - pass river valley. So when the shallow tunnel under - passes river valley,there is a high risk to bring about a lot of technical problems in the design. Taking the design of Yanshan Tunnel of Guiyang - Guangzhou Railway under - passing the Bakuang River as the engineering background, this paper researches the key design technologies for the shallow tunnel under — passing the seasonal river valley.
Research conclusions:(1) When shallow tunnel under 一 passes seasonal river valley,the main risk comes from the huge ground water inflowing into the tunnel possibly to produce the water and mud bursting and the collapse of subsurface cut tunnel and make the tunnel lining structure floating. (2) The construction risk can be much cut and structure can be safe and reliable by adopting the door - type sealed structure system composed of the secant pile, top beam, anti 一floating board,grouting to the rock in the framework and fully sealed lining structure of tunnel. (3) The working order of sealing before excavation and the effective risk control plan can ensure the construction safety and control the construction risk. (4)This study result can provide the reference to the similar projects.
胖涛,方钱宝. 浅埋下穿季节性河谷门式封闭结构设计[J]. 铁道工程学报, 2013, 30(6): 59-63.
PANG Tao, FANG Qian–bao. Design of Door - type Sealed Structure in Shallow Tunnel Under - passing Seasonal River Valley. 铁道工程学报, 2013, 30(6): 59-63.
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