Tel Aviv Subway- The Red Line

Client:                                         NTA – Metropolitan Transit System

Planning & Execution Period:       2010-2021 (under construction)

Design in collaboration with:        Geoconsult- Salzburg, Austria

Description:

The twin light rail tunnels on the Red Line are 8.5 km each, 6.50m inner diameter, 17 km total of TBM tunneling work and constitute the entire backbone of the Red Line, which is   24 km long and 10 km underground (excluding 10 stations).

After stabilizing the ground around the launching shafts, the TBM machine is launched and progressed through "cutting teeth" that cut the kurkar in the direction of progress and transfer the excavation into the body of the machine using a dedicated screw conveyor. The excavation is transported in a conveyor belt and from there it is evacuated to designated storage areas at the organization site.

The progress of the TBM is by creating a pipe made of prefabricated concrete rings. This sleeve is the final lining of the tunnels. The tunnels consist of concrete rings about one meter long, which are connected by steel connectors and screws in waterproof joints.

The concrete envelope creates a waterproof space that allows the tunnel to be executed without degrading the ground water.

The expected rate of progress of the excavation under optimum conditions, without faults, is 15-20 m per day.