3rd Bridge on Bosphorus river (Istanbul, Turkey)


The third bridge on the Bosphorus river is a cable-stayed suspension bridge with a  single span of 1400 m linking the European and Asian shores of Istanbul (Turkey). Built by the Turkish Italian consortium Içtas-Astaldi, its design was assigned to T-Engénierie in collaboration with Michel Virlojeux.

TERRASOL is currently carrying out the checking of the foundations design for SETEC TPI (Independent Checker for the project). As the first phase of this work focuses on design analysis, TERRASOL has also provided its advices for project optimisation, with the checking of the stability of the rock foundations, using 3D finite element calculations.

Constructed in a particularly demanding seismic context, the bridge lays on both shores on a rocky formation composed  of andesite and conglomerates. Each end of the bridge is composed of:
•    A 15 meters deep anchor block;
•    A block comprising 2 m deep shear keys enabling anchoring of the cable;
•    4 piers;
•    2 shafts (20 m in diameter and 20 m deep) to anchor the 320 m high pylons.

These pylons will exert considerable forces in the construction phase, under the effect of the wind and during the installation of the deck, and in the final phase, under the effect of deck tipping and seismic actions.

Terrasol’s achievements:


Independent engineer

Characteristics
PERIOD :  2013-2014
Project owner : Turkish State
Constructor : Içtas-Astaldi consortium
Client : Içtas-Astaldi
Main specifications :  

  • Bridge lenght: 1408 m
  • Pylons height: 320 m
  • Foundations of the piles: shaft 20 m deep and 20 m diameter