ABSTRACT
The secondary lining of the tunnel plays a very important role in the stability of the surrounding rock, especially when the tunnel is in a complex mountainous soft rock environment. Due to unreasonable construction and design, inaccurate surveys, and other factors, many tunnels have structural safety defects before the expiration date of their service life, which seriously affects the safety and durability of the tunnels. This research is based on the tunnel engineering of the G208 line project in Qixian County, Shanxi Province, and uses the methods of geological conditions, surrounding rock characteristics investigation, and numerical simulation to analyze the stress problems of the secondary lining. The results show that the maximum displacement and maximum stress occurred at the sidewall during construction. Therefore, special attention should be paid to the deformation of the sidewall during the secondary lining construction of the tunnel. This result will also be of great significance to the actual project.
