Feasibility Study on Step Method Excavation of Tunnels with Large Cross Section and Small Interval

Based on the analysis of monitoring data in the construction of Linwu Tunnel and the numerical simulation of construction sequences by software Ansys, the paper calculated values of ground settlement and vault settlement in program of step method excavation; and analyzed the influences between excavation program and ground settlement, as well as vault settlement. It is feasible to use the program of step method excavation in areas of V-class surrounding rocks in Linwu Tunnels with large cross section and small interval, which offers great reference value to other similar projects.