The work and the technique: Second Bridge over the Bosphorus, Turkey

The project for the new motorway connecting the city of Kinali in Thrace (Europe) with the Kazanci near the Sakarya river in Anatolia (Asia) went to a joint venture led by Impregilo S.p.A. (now Webuild).

The first involved building 62 km of motorway on the European side, from Kinali to Mahmutbey, 51 km of which has two lanes in each direction and 11 km three lanes in each carriageway.

The second lot constituted the most important section and the real technological challenge of the entire project. This involved building the second Bosphorus bridge plus 37 km of motorway links with four lanes per carriageway connected to it, two artificial tunnels, two flyovers and 14 viaducts.

The last two lots involved constructing 45 km of motorway in the Asian part from Çamlica to Gebze and 73 km of motorway in the Asian part from Izmit to Sakarya, including junctions. The latter is the longest section, and is split into two parts: a mountainous area, with tunnels connecting three consecutive viaducts, and a flat area on the northern bank of a lake, culminating in a viaduct resting on foundation piles placed in the riverbed.

With its second suspension bridge over the Bosporus, the Kinala-Sakarya motorway is one of the most important single-contract projects in the history of the Turkish Republic.