ABSTRACT
A large number of tunnels in China cross loess strata, and the deterioration of surrounding rocks during operation leads to large stress on supporting structures. Long-term performance monitoring is of great significance for the formulation of maintenance plans and the reduction of tunnel operation risks. This paper uses numerical simulation, field tests and other methods to analyze the key monitoring positions of the lining of the loess tunnel during operation. Relying on the Qiaoyuan tunnel, a long-term performance monitoring system based on distributed optical fiber is constructed. The results show that distributed optical fiber can accurately monitor lining cracks in the loess tunnel operation stage, which is of great significance to the development of maintenance plans and the reduction of tunnel operation risk.
