The Tiger Mountain Tunnel is located on the side of the contact zone of different strata. The overall lithology is poor, and it is adjacent to a number of large fault structures. Fracture zones and dissolved fissures are developed, and the geological conditions are adverse. The excavation section of the tunnel reaches 219.78m2, the minimum distance is 0.55 times the diameter of the tunnel. It is located in the main traffic area of the city and there are many interference factors. The large excavation section, high standard, and difficulty of the project are rare at home and abroad. At present, there are no standardized standards to rely and no available mature technology system. Aiming at the technical difficulties and safety risks during the construction process, a variety of methods such as theoretical analysis, numerical simulation, model tests, and field tests are used for exploration and research. Adaptive mechanized construction equipment for super-large-section tunnels is developed, the technical parameters of the excavation and support of the tunnel with a large cross section and a small clear distance are optimized, a regional monitoring method for unstable blocks is proposed and a risk management system for the entire process of tunnel construction is established. Great innovative progress has been made in the field, filling the gaps in technical results and design specifications in related fields, and serving as a unique example and valuable experience of eight-lane road construction in China.
