超大断面公路隧道斜交下穿高速铁路施工方案研究

以渝长扩能项目唐家嘴隧道为工程依托，为保证下穿段安全快速地通过，经技术经济方案比选，有限差分法数值模拟验证，确定下穿隧道最优施工方案。研究结果表明:双层初支+三台阶法具有工序简单、施工机械化程度高、工期短、经济性好等优点，对高铁路基沉降及轨道偏差的控制处于标准之内，下穿段隧道施工宜采用此方案。

Research on Construction Scheme for a Large Cross-section Highway Tunnel Obliquely Undercrossing an Existing High Speed Railway

Based on Tangjiazui tunnel in Yuchang capacity expansion project, technological and economic analysis and the finite difference simulation is used to determine the best construction scheme of tunnels undercrossing the high-speed railway so that safe and rapid construction can be ensured. The results show that double-layer supporting with three step method has the advantages of simple process, high mechanization degree, short construction period and good economical efficiency. The control of subgrade settlement and track deviation of high speed railway is within the standard. Priority should be given to this scheme for tunnel construction undercrossing the high-speed railway.