老寨隧道洞口段施工过程中的工作性状

Work behaviors of LaoZhai tunnel entrance during construction

隧道洞口通常处于浅埋、偏压、围岩破碎等复杂地质、地形条件,施工中容易发生仰坡坍塌、冒顶、衬砌结构变形开裂、难于安全进洞等情况.以厦蓉高速公路老寨隧道为例,针对浅埋、偏压及洞口段围岩破碎的情况,采用FLAC3D数值计算软件对洞口段隧道支护结构的应力、塑性区发生发展规律、变形等进行研究,得出了隧道洞口段开挖过程中应力分布规律、塑性区的分布及破坏特点、变形与隧道开挖的关系等.

many accidents Because of the shallow tunnel with unsymmetrical loadings and disintegrate structure rock mass, were taken place during mountain highway tunnel entrance construction, such as front slope collapse, roof falling, crack on shield lining and difficult to dig , etc. Analysis of three - dimensional simulation in the excavation process province of Xiamen - dimensions （ FLAC3~ ） of portal section of shallow tunnel With unsymmetrical loadings of Laozhai tunnel in Guizhou Chengdu expressway was conducted by using the fast Laragia analysis of continua in 3 program. And many useful conclusion were obtained.