新建铁路隧道小净距上跨既有隧道施工方案研究

Study on the Construction Scheme of the New Railway Tunnel Up-Crossing the Existing Tunnel with Small Clear Distance

通过对新建张吉怀(张家界经吉首至怀化)铁路邓家坡隧道上跨既有焦柳铁路黄土岗隧道的施工方案研究,按照实事求是、数变我变、动态调整的施工原则,从进入交叉点前100~50m至交叉点,分段采取优化爆破方案、及时准确收集围岩及监控量测数据、加强支护等措施,顺利通过了交叉段,同时也保证了施工进度,为消除上跨既有隧道的施工安全风险提出了相关施工经验及解决方案。

Through the study on the construction scheme of Dengjiapo tunnel of the newly-built Zhang Ji Huai(Zhangjiajie to Jishou to Huaihua)railway up-crossing the Huangtugang tunnel of the existing Jiaoliu railway,according to the construction principles of seeking truth from facts,number change and dynamic adjustment,from 100 meters to 50 meters before entering the intersection to the intersection,measures such as optimizing the blasting scheme,timely and accurately collecting surrounding rock and monitoring measurement data,strengthening support and so on were taken to successfully pass the intersection.At the same time,it also ensures the construction progress,and puts forward relevant construction experience and solutions to eliminate the construction safety risk of crossing the existing tunnel.