高水压岩溶隧道堵水限排防排水设计研究

Research on Waterproof and Drainage of Karst Tunnel with High Water Pressure Based on Blocking Groundwater and Limiting Discharge

高水压岩溶隧道堵水限排设计大多采用“两侧沟+中心沟”的边墙脚排水方式.结合应山岩隧道工程,采用数值模拟手段进行研究,得出边墙脚排水方式下仰拱衬砌水压力大、安全系数低的结构受力特征.鉴于该特征,结合寒区隧道在仰拱下设排水沟的思路,提出“仰拱下排水”的设计方案,通过数值手段研究表明该排水方式下仰拱衬砌水压力大幅度降低,结构受力状况得以改善.仰拱下排水沟建议采用矩形截面,每50m设置检查井.

Based on the idea of water plugging and drainage restriction, the side wall foot drainage mode of "two side ditches + central ditches" is mostly used in high water pressure karst tunnels. Combined with Yingshanyan Tunnel project, numerical simulation method is used to study the mechanical characteristics of the side wall foot drainage mode. The conclusion is inverted arch lining with high water pressure and low safety factor. In view of this characteristic, combined with the idea of tunnel drainage under inverted arch in cold region, the design scheme of " the central buried ditch below the arch " is put forward. The numerical study shows that the water pressure of inverted arch lining under this drainage mode decreases greatly and the structural stress characteristics are improved. The rectangular section is recommended for the drainage ditch under inverted arch, and inspection wells are set up every 50m.