Rio–Antirrio bridge

38.32138888888921.772777777778Koordinaten: 38 ° 19 ' 17 "N, 21 ° 46' 22" E

F1

A5

Gulf of Corinth

The Rio Antirrio bridge (Greek Γέφυρα Ρίου - Αντιρρίου Géfyra Riou - Andirriou ) or officially the Charilaos Trikoupis Bridge ( Γέφυρα Χαρίλαος Τρικούπης ) is a road bridge in Greece over the Strait of Rio - Antirrio ( Στενό Ρίου - Αντιρρίου ) that the entrance to the Gulf of Corinth forms. It combines Antirrio on the north shore with Rio on the Peloponnese, eight kilometers east of Patras. It caused a stir because it was considered impossible a long time to build a bridge in an earthquake zone via a 2.5 km wide and 65 m deep strait without stable ground.

Description

The information carried by four pylons cable-stayed bridge with a fan-shaped cable assemblies has two lanes with an emergency lane and a pedestrian and cycle path outside the rope fastenings in each direction.

The total 2883 m long bridge consists of a 2252 m long main bridge over the sea, the 392 m long bridge ramp for access to Río as well as the 239 m long ramp bridge at Antirrio. The main bridge has a span of 286 m, 560 m and 286 three times m. The middle two pylons are 230 meters high, they are in 65 m deep water and rise further 164 m above sea level. The two outer pylons stand in a little less deep water and reach a height of 141 m above sea level. The bridge deck is replaced by an all strait spans arching upwards. The middle passage has a clear height of 52 m. On the basis of the length of the main bridge is the second longest cable-stayed bridge in the world (after the 2460 m long Millau Viaduct ).

Technical details

The nearly 2.5 km wide and usually about 65 m deep entrance to the Gulf of Corinth has geologically to extremely difficult conditions. Even 100 m below the seabed was found not viable rock, the soil consists rather of sand, silt and clays. The entrance is located on a tectonic fault zone, which removes the Peloponnese per year by several millimeters from the Greek mainland and caused numerous earthquakes. The entrance is also known for frequent storms and has boat traffic.

The design therefore had to meet the following criteria and loads:

• Foundation in 65 m water depth on not supporting soils;
• Earthquake of magnitude 7 on the Richter scale;
• Tectonic shifts in the pillar up to 2 m in any direction over the design life of the bridge of 120 years;
• Impact of a 180,000 dwt tanker unloaded with 16 nodes;
• Impact of a 80,000 dwt bulk carrier loaded with 16 nodes;
• Wind speeds on the roadway deck of 180 km / h (50 m / s), which means that wind tunnel tests must demonstrate the flutter stability of the deck up to wind speeds of 266 km / h ( 74 m / s).

A foundation of the bridge with the conventional means of civil engineering retired from the depth of water; it had to be resorted to applied in the construction of off-shore drilling platforms techniques. First, the ground in the sites provided for the towers has been stabilized by a long steel tubes were driven with a diameter of 2 m at intervals of 7 m in each case on a circular area of ​​about 100 m in diameter up to 30 m. Each circle 200 pipes were introduced in this manner do not have the function of a pile foundation, only the soil stabilization despite the similarities. The circular areas were then covered with a 2.75 to 3.00 m thick layer of aggregates (10/ 80), which was precisely leveled to the predetermined level - at a depth of 65 m for a new challenge. This layer is intended to serve the pylons in the case of earthquakes as a plain bearing and prevent severe side impacts are transferred to the pylons.

On this plain bearing rests the foot of the pylon, which has no firm connection to the ground. It is a round concrete construction with 90 m diameter, consists of a plane base plate 9 to 13.5 m high side walls and a conically increasing towards the center cover. The construction is stiffened internally by annular walls and radially extending partitions. In this case, concrete is used with a steel portion of 300 kg / m³.

This structure supports the round concrete pillar, which in its lower part has a round, tapered profile with a diameter of 38-26 m. At the water surface, it goes into a vertical octagonal pillar, which expands under the deck to an inverted, about 15 m high pyramid, which ends in the square support of the superstructure, which has a side length of 38 m. This inverted pyramid is structurally the most difficult section of the pillar. The concrete here has a steel content of 475 kg / m³, locally even 700 kg / m³. The corners of this square are the basis for the four legs of the upper part of the pylon, which consist of 4 x 4 m wide box girders and unite in the form of an A in a high peak, in which a large metal box is placed with the cable stays.

The 27.2 m wide and 2.82 m high bridge deck is supported by a total of 368 steel cables. Each compartments on each side thus consists of 23 cables, which have lengths between 77 m and 293 m. The ropes are tight fitted over its anchoring to the roadway deck with dampers designed to prevent an earthquake uncontrolled oscillations.

The bridge deck is a composite system consisting of a steel frame with two 2.20 m high side members and all 4 m inserted cross braces and a reinforced concrete slab for the roadway. The bridge deck is continuous over its full length of 2252 m without interruptions construction. The deck is not on the piers on, but depends solely on the ropes. Thus, it is not pushed from side winds against the legs of the pylons, the damping elements are blocked. The lock rings shall they break off when a major earthquake, so that the entire deck slab can vibrate and thus compensate for the movements of the pylons. Between the ends of the bridge deck and the approach ramps extraordinarily large expansion joints have been provided that can accommodate not only the enormous thermal expansion of the long bridge decks, but also tectonic shifts. The specially developed transition structures are currently the largest of its kind

The bridge is equipped with numerous sensors and measuring instruments, which detect external influences on the bridge and their condition and route the data to the monitoring point. Here, earthquakes are detected as early as possible and the bridge if necessary automatically closed to traffic.

Individual aspects of the construction phase

To ram the steel pipes into the seabed, a barge was converted to a tension -leg platform, which has been held with steel cables in the correct position, which were attached to 750 -ton concrete blocks on the seabed. The platform was equipped with a 140 -ton crane, with which the ram was served.

Since the construction of the piers could not start in 65 m deep water were ever two pillars feet first cast in a dry dock next to the bridge, where the high construction crane was placed on the center of the bottom plate. The feet were buoyant as soon as the cover and the first approach of the rising pillar were made ​​. They were then towed to a quiet spot in the sea and continued to be built until they had reached the required height for lowering. They were then towed to its final position, lowered on her gravel bed on the sea floor and then finalized. The crane in the middle of the pillars was lifted once began with the four sloping legs of the upper part, and re- erected on the square carrier outside of the legs. The big metal box with the cable stays were welded together in the construction area on land and lifted by a floating crane as a whole to the top of the pylon. The tugs and floating cranes were provided by the Dutch company Smit.

The bridge deck was constructed from prefabricated, 12 m long segments, which were also brought by the floating crane into position and held by a specially crafted attachment apparatus until they were permanently attached to the bridge deck and the tension cables.

Architectural History

Initial ideas

The idea of ​​a connection on the western end of the Gulf of Corinth from the year 1880 by the then Greek Prime Minister Charilaos Trikoupis (Greek: Χαρίλαος Τρικούπης ). He has already brought in 1880 in the Greek parliament the proposal to build a bridge across the Gulf at Patras. The realization of this vision, however, were from the beginning, great technical difficulties in the way. Nevertheless Trikoupis commissioned in 1889 (the year was completed in the in Scotland Firth of Forth Railway Bridge ) Greek engineers to investigate the possibility of building a bridge from Rio to Antirrio. Although the former technicians possibilities as soundings on the seabed or seismic records of the tectonic activity is not known and thus the actual difficulties were not fully aware of this, they had to capitulate to the local conditions. The Gulf of Corinth at its narrowest point, after all, still a width of about 2.5 km away and the water is up to 65 meters deep. Also, there are very strong currents at Patras, and it comes in the region again and again to earthquakes and violent storms. After damaligem prior art, therefore was to build a bridge out of the question, and the engineers had the Prime Minister of the disappointing results of their investigations to inform. The idea disappeared for over 100 years in the drawers.

Even in 1992 came the Greek Technical Chamber in a re-examination at the conclusion of the construction of a bridge at this point was nearly impossible. The expertise had shown more difficulties in addition to the already known issues. The biggest obstacle was the totally inadequate foundation conditions on the seabed. The entire subsoil consists of sand, silt and debris, and even with drilling to over 100 meters depth was not sufficiently stable rock are found. The seismic activity were examined and also gave little cause for optimism: Within 100 years, there had been seven earthquakes of magnitude 4.5, and also drifts of Peloponnese each year by several millimeters away from the mainland. When a violent earthquake, the distance in extreme cases could increase by one to two meters. Another problem was the first since the investigation greatly increasing ship traffic, which required for the bridge a height of over 50 meters and a large wingspan.

Despite the negative judgment of the Greek Technical Chamber of the vision of building the bridge was now no longer to stop. However, had to be found because of the particular difficulties for completely new unusual solutions and methods of construction. The Charilaos Trikoupis bridge was therefore a technically very interesting and innovative building in which many details broke new ground.

Tendering, contracting and contract structure

In 1992 the project was awarded within the framework of an operator model on the basis of a concession by the Greek government over 42 years. It was the first concession project of the Greek state. The concessionaire should plan and build the bridge in the first seven years and operate in the following 35 years and maintain. Since the future revenues from the bridge toll is not sufficient to finance the bridge, next to a seed funding from Greece a loan from the European Investment Bank was required, but did not want to participate in the construction risks themselves. The 1993 output range of the French group Vinci was successful.

After extremely complex negotiations on 3 January 1996, the concession agreement between the Greek government and founded especially for this project Franco-Hellenic Society Gefyra SA signed, which finally came into force after the completion of the financing contracts on 24 December 1997.

The nearly two- year-long period between signing the contract and the entry into force was used by the engineers to once again discuss the project with outside experts and to review what led to some fundamental changes.

The concession company Gefyra S. A. Vinci are involved with 57,45 % and the Greek companies actuator Concessions with 22.02 %, J & P Avax with 12.14% and 8.39% with Athena. The Gefyra S. A. commissioned the joint venture Kinopraxia Gefyra ( Vinci Construction Grands Projets also founded for the project 53.00 %; ACTUATOR 15.48%; J & P Avax 11.20%; Athenas 7.74%; Proodeytiki 7.74%; Pantechniki 4.84 %) with the planning and construction of the bridge. The Gefyra Litourgia S. A. ( with the same shareholders as the Gefyra SA) was commissioned by her with the operation, maintenance and repair of the bridge.

Design and planning

The design of the project and its engineering planning was associated by Vinci Construction Grands Projets and group companies such as Freyssinet International. Vinci worked closely with the engineering Ingerop, Géodynamique & Structures and Domi (Greece) and many other experts. Berdj Mikaelian from the office Ingerop served as architect for the outer shape of the bridge.

As a Design Checker, so as an independent checking engineer, the Canadian engineering company Buckland & Taylor Ltd. was. commissioned from Vancouver, which was reinforced by a number of American specialists such as Dr. Peck, Dr. Dobry or Dr. Priestley and Dr. Seible. As a Supervision Engineer, so the construction supervision, the British Office Faber Maunsell Limited was commissioned. Both had not only its client Gefyra SA to report, but also to convince the Greek government and the banks involved that the project was properly planned and executed.

Construction

The groundbreaking ceremony took place on 19 July 1998 from the Greek Prime Minister Konstantinos Simitis. In June 2004, the last segment of the bridge deck was used. The cost of the project amounted to 771 million euros. The bridge was on 7/8 August 2004 officially opened with great ceremony and a fireworks display - in time for the August 13 commencing Olympics, but a good four months before the contractual completion date. During this ceremony rendered as torchbearers Otto Rehhagel, the coach of the Greek national football team, Irena Szewinska, the Polish Olympic Champion, and Stratos Apostolakis, coach of the Greek football team for the Olympic Games, the Olympic flame across the bridge. On August 12, the bridge was opened to traffic.

On the site up to 1200 people were working simultaneously in the top. Nevertheless, there were in the work up to 165 m altitude during the five-year construction period not a single serious accident with permanent physical damage.

Visible cross-section ( 2002)

Detail ( 2002)

Pattern of the rope anchorage ( exhibited in Museum bridge )

View from Antirrio on the bridge almost finished (2004)

Suspension ropes

Uptime

On 28 January 2005 the bridge for safety reasons was initially closed for an indefinite period. After thunderstorms and storms with wind force 9 of the 368 suspension ropes had been advised and severed on fire. On February 1, the bridge was reopened to traffic, but until the end of the exchange of the support cable with only one lane in each direction. Meanwhile, the bridge is four lanes for traffic again.

In 2006, the building and the project architects and engineers received the " Outstanding Structure Award" of the IABSE.

The operation time is 24 December 2039-42 years after the entry into force of the concession contract. The bridge must then be handed over to the Greek government in a contractually fixed state.

Location

While the east of the Greek mainland is relatively well developed, the sparsely populated and mountainous north-west of the country was almost impossible to achieve by major roads and railway connections. In the late 1990s, two major highway construction projects were started, which should improve the connectivity of the Northwest and begin in Ioannina. These are the east-west axis A2 ( Egnatia Odos ), which connects the Epirus with Macedonia and Thrace ( this is largely completed ), as well as a north- south link the A5 ( Ionia Odos ). The Rio Antirrio bridge will connect the future with the existing A5 A8 in the Peloponnese, by then, the bridge is listed as National Road ( blue signs).

The place Rio is an eastern suburb of Patras and since 1998 a city incorporations ( Dimos ). Here is the campus of the University of Patras. In addition to the highway there is a railway station of the Peloponnesian meterspurigen. The under construction regelspurige new line will have a breakpoint in Rio.

The place Antirrio is much less significant than Rio and concerns has always been just his role as a transition to the Peloponnese and as a port.

Use

Car drivers have to pay the end of 2012 for a single journey across the bridge € 13.20, € 19.90 to € 41.00 trucks ( 5 axles) and for buses (depending on seats ) € 29.70 to € 64,00 demands. For pedestrians and cyclists crossing the bridge is free.

Until the construction of the bridge stood for the crossing of the estuary only ferries available. The owner of the ferry boats were compensated, but may continue to operate the route. The crossing (about 45 minutes ) costs half of the bridge toll and offers a view of the bridge.