水工长隧洞小断面开挖爆破施工技术研究

Research on small section excavation blasting construction technology of hydraulic long tunnel

对于高流速的水工长隧道来说,为了减小隧道环境内滤气与冲击波的不良影响,隧道洞身后续必须通过修建衬砌的方式来承受围岩压力以及内水压力,因此隧道小断面施工必须采用一种“光面爆破”技术,以确保隧道洞身岩体的平整性要求。文章以某地引水隧道工程的施工项目为例,对小断面开挖的光面爆破方案设计、爆破施工技术中洞内炮眼布置、装药量控制、排气通风以及排水布置等重要工序的施工要点进行了分析解读。

For long hydraulic tunnel with high flow velocity,in order to reduce the adverse effects of air filtration and shock wave in tunnel environment,the tunnel must be built by lining to bear the surrounding rock pressure and internal water pressure,therefore,it is necessary to adopt a“Smooth blasting”technique in the construction of tunnel with small cross-section to ensure the smoothness of the rock mass of tunnel body.Therefore,taking the construction project of a water diversion tunnel as an example,the smooth blasting scheme design of small-section excavation,blasting construction technology in the hole layout,charge control,exhaust ventilation and drainage layout,and so on important working procedure construction main point has carried on the analysis explanation.