Abstract: In the construction of long tunnels, vertical shafts are always installed. The muckingout and material supplying through the vertical shafts are slow, which leads to slow tunneling advance. Therefore, access ramp are proposed to facilitate the tunneling. In the paper, the feasibility of the proposal is numerically simulated by means of largescale finite element software. The construction scheme is optimized according to the simulation results. Detailed monitoring program is established according to relevant standards and monitoring is executed during construction. The construction practice and the monitoring data show that the optimized program is rational and economical, the safety of the tunnel and the access ramp is guaranteed and the construction period is shortened.

Key words: long tunnel, access ramp, vertical shaft, numerical simulation, monitoring