Millau ViaductA detailed look into its constructionJoseph Rei Mark CoCE 124

OverviewA cable-stayed road bridge that links the motorway from Paris to BarcelonaDesigned by French bridge engineer Michel VirlogeuxLongest cable-stayed deckTallest vehicular bridge in the world

Overview

Significance of the Project1980sFrance built A-75 motorway that links Paris and Spain Before two roads can meet, they reach one of the deepest valleys in France Motorists have to make a detour into Millau vicinity

Significance of the ProjectRoute map of the A-75 Motorway

Significance of the ProjectCETE Mediterrane-assigned to conduct the preliminary studies to determine the route of the highway

4 Possible RoutesYellow Route - Great EasternBlack Route Great WesternRed Route near RN9Blue Route - Intermediate

Significance of the ProjectMap of the Possible Routes

Significance of the ProjectOpposition to the ProjectWorld Wildlife FundFrance Nature EnvironmentNational Federation of Transport Users AssociationReasons of opposition:Route to the west is betterObjective of the viaduct will not be achievedRevenues collected will never equal initial investmentLevel of difficulty of construction is so highViaduct will cause a deviation

Technical DesignA pool of international experts was established-chaired by Jean-Francois CosteFebruary 1995-proposals were narrowed to five general designsJuly 15, 1996-a decision was made by the jury chaired by Christian Leyrit

Technical DesignDesign chosen was the cable-stayed bridgepresented by Sogelerg, Europe Etudes Gecti and Serg and the architects Foster + Two major challenges:1. Crossing the Tarn River2. Making two plateaus meetSolution:-Uses seven pylons

plans were approved near the end of 1998

Contractors1999-international call for tenders was issued

Compagnie Eiffage du Viaduc de Millau (CEVM) -led by Eiffage-won the bidding

ContractorsOther consortia who participated in the bidding:

A consortium led by the Spanish company Dragados, with Skanska (Sweden), and Bec (France)

Socit du Viaduc de Millau, including the French companies ASF, Egis, GTM, Bouygues Travaux Publics, SGE, CDC Projets, Tofinso and the Italian company Autostrade

A consortium led by Gnrale Routire, with Via GTI (France) and Cintra, Nesco, Acciona et Ferrovial Agroman (Spain).

ContractorsBreakdown of roles in the construction work:Eiffage GroupEiffage TP concreteEiffel steel roadwayENERPAC hydraulic launching systemEiffage (pre-stress division) prestressing of pillar headsEiffage Concessions management

ContractorsPERI sliding shutter for the piersPAECH Construction Enterprise (Poland) pylonsAppia bituminous coatingForclum electrical installationsFreyssinet, subsidiary of the Vinci Group stay-cablesGreisch (Belgium) steel deckSetec engineering group project authoritySocit Nationale des Chemins de fer franais (SNCF) exhibit partial control of the project

Stages in ConstructionDecember 14, 2001-first stone was laid

December 16, 2004-viaduct is opened to the public

Stages in ConstructionRaising the Piers- each pier was supported by 4 deep shafts, 15 meters deep, 5 meters in diameter-16, 000 tons of steel bars were used

Parts of the viaduct

Stages in Construction-every three days, each pylon increased in height by 3 meters

Table 1: Height of the Piers

Stages in ConstructionB. Launching the Deck-The operation was automated by Buonomo with a welding robot and plasma cutting machine.

-This was the longest launch ever attempted over the highest piers in the world.

Stages in ConstructionDiagram of launching the steel roadwayLegend: (P) Pier, (T) Temporary steel tower, (C) pier support

Stages in ConstructionC. Meeting at the JunctionMay 28,2004-north and south deck met

-result of 21 months of intense work

Stages in ConstructionD. Installing the Pylons

-Each massive pylon measure 90 meters high and weighs 700 tons.

Anchorage of pylon to the pier

Stages in ConstructionE. Installing the Stay-cables-the 154 stay-cables are expected to protect roadway from sagging or collapsing

-stays can be composed of 55 to 91 high tensile steel cables Tensioning of the steel strands

Stages in ConstructionF. Installing the Electrical System-30km of high-current cables, 20km of fiber optics10km of low-current cables and 357 telephone sockets were installed

-viaduct also employs the state of the art in terms of instrumentation

Stages in ConstructionG. Laying the Road Surface-The team from Appia laid a special bituminous surface to the road

-The road surface added 10,000 tons to the load carried by the bridge.

Timeline in Construction

December 14, 2001Laying of the first stoneDecember 16, 2001Work beginsJanuary 2002Laying pier foundationsMarch 2002Start of work on the pier support C8 June 2002support C8 completed, start of work on piers July 2002start of work on the foundations of temporary, height adjustable roadway supports

August 2003start of work on pier support C0 September 2002assembly of roadway begins

Timeline in Construction

November 2002first piers complete February 25-26, 2003laying of first pieces of roadway November 2003completion of the last piersMay 28,2004meeting of the roadways at the junction2nd half of 2004installation of the pylons and shrouds, removal of the temporary roadway supports December 14, 2004official inauguration December 16, 2004opening of the viaduct (ahead of schedule)

January 10, 2005initial planned opening date