Japanese Team Goes Deep To Link Istanbul's Two Parts

摘要

Sections of the world's deep-est sunken tube tunnel are emerging from dry docks on the Marmara Sea coastline, east of Istanbul. Destined to lie under nearly 60 meters of water, the 1.4-kilometer-long twin tube will carry a new $3-billion urban railroad under the Bosporus water-way, to link the Asian and European sides of the Turkish city. Nearly 2,200 cu m of concrete was cast early last month into the base slab of the first of 11 tube elements at Tuzla, some 25 km from Istanbul. Preparing for the elements' arrival, the contractor is treating soil along the Bosporus route to improve its seismic behavior.