车行横洞施工对隧道主洞变形的影响

Influence of Horizontal Adit Tunnel Construction on Main Tunnel Deformation

针对隧道车行横洞施工对主洞结构产生影响,以运城-灵宝高速公路中条山隧道工程为依托,采用现场试验和三维有限元仿真的方法,对车行横洞施工阶段主洞的变形规律进行了研究。研究结果表明:车行横洞施工对主洞的影响,在时间上主要表现在交叉口初支拆除和横洞的第1个开挖步,随着横洞开挖深度的增加,主洞结构的变形逐步趋于稳定;车行横洞施工对隧道主洞围岩变形影响主要表现为主洞拱顶下沉量增加和开挖侧拱脚水平位移减小,主洞未开挖侧拱脚水平位移影响不大。

For the influence of horizontal adit construction on the main tunnel deformation,the Zhongtiaoshan highway tunnel engineering of Yuncheng-Lingbao highway is taken as an example.The field test and 3D finite element simulation are adopted to study the deformation regularity of main tunnel during the horizontal adit construction stage.The research results are shown as follow：The significant effect of horizontal adit tunnel construction on main tunnel deformation mainly occurs when demolishing initial support in intersection and during the first excavation step.The deformation of main tunnel is stable with the increase of excavation depth of the horizontal adit.The effect of horizontal adit tunnel construction on main tunnel deformation is mainly the increasing of the vault deflection of the main tunnel and the decreasing of horizontal displacement of the arch springing in excavation side.The effect on the horizontal displacement of the arch springing in the other side is small.