Abstract
The project of railway tunnel construction across the Bosphorus Strait in Istanbul, Turkey is known as one of the most interesting projects that connects Asia with Europe, and consists of tunnels constructed in three different methods: immersion, TBM and NATM. Istanbul is the largest city in Turkey with a population of over 15 million. And this city is divided by Bosphorus Strait. With only two east-west bridges connecting European side and it Asian side, this resulted in chronic congestion with increased air pollution. To relieve these problems, construction work on a subway tunnel under the strait was begun in 2004 under an EPC (Engineering, Procurement, and Construction) turnkey contract with Japanese financial backing. This concept was imagined 150 years ago in Turkey and we can see from the design drawing illustrated by a civil engineer in 1860.
