RIO-ANTIRIO BRIDGE

The 'Rio-Antirio bridge' (Greek: ''Γέφυρα Ρίου-Αντίρριου''), officially called '"Charilaos Trikoupis"' bridge after the statesman who first envisioned it, is a cable-stayed bridge crossing the Gulf of Corinth near Patras, linking the town of Rio on the Peloponnese to Antirio on mainland Greece.

Contents

Improved communications

History

Engineering Feats

Trouble with cable links

External links

Improved communications

The long bridge dramatically improves access to and from the Peloponnese, which could previously be reached only by ferry or via the isthmus of Corinth at its extreme east end. Its width is 28 m — it has two vehicle lanes per direction, an emergency lane and a pedestrian walkway. Its five-span four-pylon cable-stayed portion of length is the world's second longest cable-stayed deck; only the deck of the Millau Viaduct is longer at . However, as the latter is also supported by bearings at the pylons apart from cable stays, the Rio-Antirio bridge deck might be considered the longest cable-stayed "suspended" deck.
This bridge is widely considered to be an engineering masterpiece owing to several solutions applied to span the difficult site. These difficulties include deep water, insecure materials for foundations, seismic activity, the probability of tsunamis, and the expansion of the Gulf of Corinth due to plate tectonics.
Its official name is the 'Charilaos Trikoupis Bridge'. Charilaos Trikoupis was a 19th century Greek prime minister, and suggested the idea of building a bridge between Rio and Antirio; however, the endeavour was too expensive at the time, when Greece was trying to get a late foot into the Industrial Revolution

History

The bridge was planned in the mid-1990s. Site preparation and dredging began in July 1998, and construction of the massive supporting pylons in 2000. With these complete in 2003, work began on the traffic decks and supporting cables. On May 21, 2004, the main construction was completed; only equipment (sidewalks, railings, etc.) and waterproofing remained to be installed. The bridge was finally inaugurated on August 7, 2004, a week before the opening of the 2004 Summer Olympics in Athens -- and the Olympic torchbearers were the first to officially cross its length. One of them was Otto Rehhagel, the German football coach who won the Euro 2004 Championships for Greece. Another one was Costas Laliotis, the former Minister of Public Works during whose term the project had begun.

The total cost of the bridge was about € 630,000,000, mostly funded by the European Union, and it was finished ahead of its original schedule, which had foreseen completion between September and November 2004, and within budget.
The structure was built by a consortium led by the French group ''Vinci'', and which includes the Greek companies Hellenic Technodomiki-TEV, J&P-Avax, Athena, Proodeftiki and Pantechniki. It will operate it under concession under its ''Γ.Ε.Φ.Υ.Ρ.Α.'' or 'Γ'αλλο'ε'λληνικός 'Φ'ορέας 'Υ'περθαλάσσιας Ζεύξης 'Ρ'ίου- 'Α'ντιρίου (G.E.F.Y.R.A., Greek for "bridge", French-Greek Carrier of Oversea Connection of Rio-Antirio) subsidiary. The lead architect was Berdj Mikaelian.

Engineering Feats

Due to the peculiar conditions of the straits, several unique engineering solutions needed to be considered. The water depth reaches 65 m, the seabed is mostly of loose sediment, the seismic activity and possibility of tectonic movement is significant, and the Gulf of Corinth is expanding at a rate of about 30 mm a year. For these reasons, special construction techniques were applied. The piers are not buried into the seabed, but rather rest on a bed of gravel which was meticulously leveled to an even surface (a difficult endeavor at this depth). During an earthquake, the piers should be allowed to move laterally on the seabed with the gravel bed absorbing the energy. The bridge parts are connected to the pylons using jacks and dampers to absorb movement; too rigid a connection would cause the bridge structure to fail in the event of an earthquake. It was also important that the bridge not have too much lateral leeway either so as not to damage the piers. There is provision for the gradual expansion of the strait over the bridge's lifetime.

Trouble with cable links

In February of 2005, 6 months after the opening of the bridge, one of the cable links of the bridge snapped from the top of the M3 pylon and came crashing down on the deck. Traffic was immediately halted. The first investigation claimed that a fire had broken out on the top of the M3 pylon, after a lightning strike in one of the cables. It was later discovered that friction from the cable vibrations ignited the oil inside the cable used to lubricate the inner steel wire strands.There was also a risk of heavy rainfall during the season which caused rain droplets to slide down the wires resulting in their oscillation; this was eliminated by making circular grooves in the wires so that droplets could follow this path and thus keep the wire stable.

External links

★ Gefyra S.A. - official site

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★ Articles showing articulationsWebsite in French

★ Video of the bridge taken from cruise ship