OREANDA-NEWS. SK E&C announced that the company completed building of the Tunnel Boring Machine (TBM), which is the core machine to bore the Turkey Istanbul Undersea Tunnel (Eurasia Tunnel) that connects Asia and Europe and TBM will be in use for construction soon.

This machine, named as YILDIRIM BAYEZID, is one of world’s biggest tunnel boring machines with 13.7 meters in cross-sectional diameter, which is as high as a 5-story apartment, 120 meters in length, and 3,300 tons in weight. Bayezid is the name of the great Sultan who led the golden age of Ottoman Empire. Yildirim is the nickname of Bayezid and it means the thunderbolt in Turkish.

An official of SK E&C said, “This TBM was named YILDIRIM BAYEZID to symbolize that the Eurasia tunnel will spread out into Europe beyond Asia. It will be dispatched into the construction site soon after it gets transported.”

It took 15 months to design and build this TBM and it will take five more months to bore the tunnel. It will take five weeks to dissemble and pack the TBM in the German company, another five weeks to ship to Turkey, and additional three months to assemble the TBM at the construction site. The price of the TBM is very expensive to account for 10% of the total construction cost. SK said that the shipping cost alone from Germany to Turkey exceeds KRW 2 billion.

The TBM consists of the main body and the rear equipment body. The 13.5m long main body is made up of the cutter head, the cutter, the thrust, and the segment installation equipment. The segment is a concrete structure installed inside the wall of the tunnel. The rear equipment body consists of the equipment that operates and monitors the TBM, a crane that transports the segment, and pipes and pumps that discharge special chemicals mixed with debris to the ground.

The TBM method used in the Eurasia tunnel construction is to dig a tube-like passage by pressurizing, crushing, and cutting the rocky soil using a cutting head powered by the thrust system and simultaneously placing segments in the inner wall of the tunnel. As it is possible to excavate and to build tunnel structures at the same time, this advanced method can reduce the construction period and secure stability. SK E&C is planning to excavate for 17 months by averaging 6.6m per day. The total TBM length is 3.34km and the water pressure is 11 times higher than atmospheric pressure.

Lee Choong-woo, President of SK E&C Infra Biz, said, “We are looking forward to the moment when Asia and Europe are connected through the undersea tunnel constructed by SK E&C. We will successfully complete the world’s first intercontinental undersea tunnel construction in SK’s name.”

The Eurasia Tunnel Project is to connect the Bosporus Strait, which divides Asia and Europe, with an undersea twin-deck tunnel. The total length of the tunnel is 14.6km including side approaches, and the TBM tunnel is 3.34km. The total construction cost is USD 1.24 billion (KRW 1.39 trillion). After the construction completion in April 2017, SK E&C will participate in operation of the tunnel for 25 years.