Shield Tunneling - Akkerman

Shield Tunneling

Shield Tunneling

Excavator shield tunneling is a trenchless method used for larger diameter utility and crossing tunnels. This specialized form of tunneling includes a steerable forward shield with a hood that extends beyond the excavating face for ground stabilization. The material at the face is excavated by a digger arm that is controlled by an operator inside the shield. As the pipe string advances in the pipe jacking mode or propelled by a jacking can in a ring building mode, the leading edge of the shield scarifies the ground while the excavator’s arm moves material onto the conveyor belt for removal. A hydraulically controlled steering joint allows the onboard operator to make line and grade adjustments when dictated by the tunnel laser mounted in the launch shaft.