The Izmit Bay suspension bridge to be built in record time

COWI will serve as consultant for the Japanese contractor IHI, which will build a bridge spanning Izmit Bay in Turkey over the next four years. Upon completion, the bridge will be the world’s fourth longest suspension bridge

COWI has been awarded the contract for detailed design of the Izmit Bay Bridge in Turkey in cooperation with the Japanese contractor IHI.

The bridge, which is part of a new, extended highway system which links the two Turkish metropoles Izmir and Istanbul, will be the world’s fourth longest suspension bridge upon completion.

Complex bridge project

The suspension bridge over Izmit Bay is an extremely complex project with a free span of 1550 metres between its pylons and a total length of about three kilometres. The pylons will be made of steel and have a height of 250 metres.

The overall construction will require some 85,000 tonnes of steel and about 125,000 m3 concrete and is scheduled to be completed in only three years - record time.

Earthquake-resistant suspension bridge

Izmit Bay Bridge will be built in one of most seismically active areas in the world, which places additional demands on the bridge’s design. 

The bridge will be made earthquake-resistant by building its pylons on a concrete foundation that rests on a large gravel bed the pylons can slide on in the event of a major earthquake. 

This way, the suspension bridge will be partly isolated from the enormous energy released by an earthquake.

Background on the Izmit Bay Bridge

The overall price for the bridge will be about EUR 800 million.

Construction is expected to commence in the beginning of 2012 and will be completed in 2015. COWI will provide consultancy services during the entire period.

The Danish firm is the architect of the suspension bridge.

Dissing+Weitling is the architect of the suspension bridge.



LAST UPDATED: 31.03.2017