The line runs for 13km and will require 11 stations and associated NATM connections. It will form a second north to south rail corridor under the densely-populated Anatolian side of Istanbul and will be located entirely underground at an average depth of about 30m
The TBMs have versatile mixed-face dome-style cutterheads with an opening ratio of about 35%, which has proven to work effectively in Istanbul’s mixed geology – which includes low-strength sandstones, siltstones, limestones and shales. The TBMs will also be equipped with tungsten carbide soft ground cutting tools that are interchangeable with 17’’ roller disc cutters, high torque screw conveyors and active articulation systems.
