强风化花岗岩隧道洞口段施工安全技术研究

Study on construction safety technology of tunnel portal section with strongly weathered granite

依托金家庄隧道工程,针对强风化花岗岩隧道洞口段施工安全,采用中隔壁(CD)法和三台阶预留核心土法两种施工方法进行数值模拟研究,通过对比分析了两种工况下隧道位移、初期支护结构受力、二次衬砌结构受力。结果表明,采用三台阶预留核心土法施工更为合理。该研究成果可为隧道洞口工程施工提供一定参考。

Relying on the Jinjiazhuang tunnel project,two construction methods,the Center Diaphragm( CD) method and the three-step core-soil method,are adopted to conduct numerical simulation study. The tunnel displacement,stress field of surrounding rock,structure stress of initial support,structure stress of secondary lining and safety factor of rock are compared and analyzed under two working conditions. The results show that it is more reasonable to adopt the three-step core-soil method. The research results can provide some references for portal construction of tunnel.