Analysis of surrounding rock deformation in large section tunnel with different control technology crossing fault zone

: Aiming at solving the deformation of surrounding rockmass when large-section tunnels pass through faults, the construction method of No. 2 Cajianweishan tunnel of Shugang Passage in Haicang is optimized, and the original design method and optimization method for the construction process are simulated numerically by FLAC3D. The deformation of surrounding rock caused by construction under above two methods during tunnel excavation is compared and analyzed. The results show that the deformation is almost equal in above two construction methods when crossing the fault, but the optimized construction method can provide enough working space when excavating the No.2 and No.4 heading and effectively avoid the problem of pass of construction vehicles due to the setting of the inverted arch trestle. Considering the construction schedule, it is more advantageous to adopt the optimized construction method in the fault zone. The study can provide a reference for the tunnel engineering with similar geological conditions in the future.