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Marmaray Railway Tunnel

The Marmaray Project consists of a suburban rail system that establishes a connection between Istanbul Halkalı and Gebze. The project interconnects the city’s European and Asian Sides by a 1387 meter long railway tunnel constructed under the Bosphorus strait. The overall length of the rail system is 76 km. The Bosphorus will be crossed by an immersed tube, assembled from 11 sections with lengths varying between 98,5 and 138 meters. With a depth of 56 meters, these tube sections will comprise the world's deepest undersea immersed tube tunnel, earthquake-proof against magnitudes of 10.

DURABET® concrete is a high performance concrete resistant to severe exposure conditions, impermeable and it has low crack risk, low heat development properties. The choice of material allows a durable and safe tunnel for many years without maintenance.

CEM I 42,5 N type low alkali cement is produced exclusively for DURABET® by Bolu Cement Factory, a part of OYAK Cement Group. All aggregates are obtained from special resources after petrographic analysis.

03 November 2016

Key Facts

  • Country: Turkey
  • Concrete: Appr.1.000.000 m3 (Mostly DURABET® C40)
  • Cement Type: OYAK Bolu Cement- CEM I 42.5 N (SR-Low Alkali)