St. Petersburg Metro
Main features of tunnel:
- 150 meters long
- Use of industrial methods
- Reinforcement on the profile of section and on the entrance
Design of an access tunnel to the metro system
The design regarded an access tunnel to the St. Petersburg metro, to be constructed using industrial methods.
The tunnel designed has a length of about 150 m and starts from an existing circular shaft about 70 m deep. All the equipment and materials needed for excavation and to remove excavated material are to be lowered in, lifted out and supplied from the existing shaft.
The tunnel designed is to be dug with consolidation at the section edges and on the face.
The excavation of the first stretch of tunnel (approx. 300 m in length from the shaft axis) is to be carried out with traditional methods (manual digging of successive sections with temporary face and wall support), in order to create a sufficiently large working chamber to assemble and maneuver the working tools.