大断面纯黄土公路隧道施工技术研究

黄土在受水浸蚀后结构迅速破坏而引发的湿陷现象,对隧道的安全稳定和正常使用产生巨大影响。加之大断面隧道开挖过程中,对土体扰动大,极易发生地表开裂、拱部下沉、衬砌变形甚至塌方等严重问题。我国目前在大断面纯黄土公路隧道施工领域还没有成熟的经验可借鉴。本文结合神府高速公路大断面黄土隧道施工,总结出浅埋段采用双侧壁导坑开挖,深埋段根据地质情况分别采用双侧壁导坑法、单侧壁导坑法和三台阶七步流水法进行施工,并分析了三种工法的优劣和适用条件,为同类工程提供借鉴。

RESEARCH ON CONSTRUCTION TECHNOLOGY OF LARGE SECTION PURE LOESS HIGHWAY TUNNEL

The rapid destruction of the structure due to wet loess after water erosion caused by the trapping phenomenon,a huge impact on security,stability and normal use of the tunnel was produced. Coupled with the large section of tunnel excavation process,the large soil disturbance,prone to surface cracking,sinking arch lining deformation and even landslides. Now for large section of pure highway tunnel construction field,there is no matured experience. Combined with a large section loess tunnel construction of Shenfu highway,it was summed three construction methods and their merits & demerits,which provide experience for similar projects.