Shield machine application principle

Tunnel Boring Machine: In China, it is customary to use the shield for the soft soil layer and the rock formation for the rock formation.
Tunnel construction with shield machine has high automation, manpower saving, fast construction speed, one hole, no weather influence, ground subsidence during excavation, reduction of impact on ground buildings and underwater excavation It does not affect the characteristics of ground transportation. In the case of long tunnel hole and large buried depth, it is more economical and reasonable to use shield machine construction.
The basic working principle of the shield machine is that a cylindrical steel component is pushed forward along the axis of the tunnel to excavate the soil. The housing of the cylindrical assembly is a shield that temporarily supports the excavated unlined tunnel section, withstands the pressure of the surrounding soil layer, and sometimes withstands groundwater pressure and blocks the groundwater. Excavation, earthmoving, lining and other operations are carried out under the cover of the shield.