高风险铁路隧道跨越巨型暗河溶洞施工处治技术

Treatment Technology of High Risk Railway Tunnel Crossing Giant Underground River Karst Cave

为解决玉京山铁路隧道施工中揭示的巨型暗河溶洞体量大、洞壁稳定性差、底部基础薄弱,落石危险时有发生的诸多难题,降低施工风险,满足隧道结构安全和基础稳定性要求,在综合考虑技术可行性、施工运营安全性等方面的基础上,经方案比选,提出了“小范围新增泄水洞、连续梁+分层回填+洞壁防护”的综合处治方案。通过施工过程中对隧道结构变形、土体沉降监测,表明上述处治方案有效,提高了巨型暗河溶洞的整体稳定性,解决了岩溶大厅线路跨越的问题。

In order to solve many problems brought by the giant underground river karst cave revealed in the construction of Yujingshan Railway tunnel with a large volume,poor wall stability,weak bottom foundation,and the risk of falling rock often occured,the giant underground river karst cave,reducing the construction risk,satisfy the tunnel structure security and foundation stability,on the basis of comprehensive consideration of technical feasibility,construction and operation safety,the comprehensive treatment scheme of"adding drainage tunnel in a small area,continuous beam+layered backfilling+cavity wall protection"was put forward after the scheme comparison.The monitoring of tunnel structural deformation and soil settlement during construction show that the above treatment scheme effectively improves the overall stability of the giant underground river karst cave and solves the problem of karst hall line crossing.