The Rion-Antirion Bridge: Concept, Design and Construction

Opened to traffic in August 2004, the Rion-Antirion Bridge crosses the Gulf of Corinth near Patras in western Greece. It consists of an impressive multi cable-stayed span bridge, 2,252 m long connected to the land by two approaches. An exceptional combination of physical conditions made this project quite unusual: high water depth, deep strata of weak soil, strong seismic activity and fault displacements. In addition a risk of heavy ship collision had to be taken into account. The structure has been designed in view of challenging the earthquakes and ensuring the every day serviceability of the link as well. To make the bridge feasible, innovative techniques had to be developed: The strength of the in-situ soil has been improved by means of inclusions; the bridge deck has been suspended on its full length, and therefore isolated as much as it can be. Due to high water depth, construction of the main bridge of the Rion-Antirion Crossing had to face major difficulties. In relation with this, foundation works, including dredging, steel pipe driving, but also precise laying of the required gravel bed under the pylon bases, were forming an impressive work package requiring unusual skills and equipment. To achieve this task, the conceptual design of the entire structure made it possible to simplify, in terms of implementation and reliability, the concept of huge shallow foundations and to prefabricate the major components of a bridge in the most favourable conditions, combining the latest technologies available in the construction of concrete off-shore oil drilling platforms and large cable stayed bridges.