Abstract: A segment of cut-and-cover tunnel is parallel to the existing Nanning-Guangzhou high speed rail which is under construction. The distance from the edge of the track to the edge of the excavation is 20.5 meters. It is concluded that impact of the cutandcover tunnel construction on the existing high speed rail should be evaluated. The safety evaluation criteria are established from the various design codes and existing construction practice. A typical section that represented the worst case scenario (distance between the excavation and the rail track, large excavation depth and unfavorable subsurface conditions) was selected for the finite element analysis. The influence of the active and inactive rail track on the cut-and-cover tunnel excavation were simulated.

Key words: Adjacent Rail Lines, Tunnel Construction, Safety Standards, Subgrade Settlement and Tilt, Influence