• Competition


  • Competition


  • Competition


  • Competition


The viaduct over the A9 in Rennaz crosses the A9 motorway and the local RC 780 road with a total span of 350 m. In this clogged area, integration was obtained with unity and lightness.

The bridge has eleven spans that are generally 33 m long, but extend up to 34.8 m to cross the motorway.

The 1.40 m high deck follows the road profile with a deck slab reinforced with two longitudinal ribs. These ribs integrate the longitudinal prestressing cables. The whole transversal section is shaped like an aeroplane wing with close ribs, significant cantilevers and pipes hidden between the two ribs.

Each of the two ribs is supported by one of the branch of the V-shaped piers. To accommodate the local topography, the batter of the piers varies.
The abutments are partially integrated in the embankments with inclined wingwalls aligned with the outer faces of the deck curbs.

Given the loads and soils involved, piles were needed for all piers and abutments. The piles were either driven or drilled depending on available space, limited by aerial electricity cables.

Each span was built using a gantry supported on the permanent pier foundations to reduce the risk of settlement. Once the span concreted and prestressed, the gantry is moved to the next span. The span crossing of the A9 motorway is built with a gantry placed above the deck, to preserve the motorway clearance during the works.

The viaduct unwinds its curve, fitting smoothly into the Rhône valley countryside.

The viaduct won the swiss architectural award DRA 3 / 2014.

  • Owner

    Road Department of Canton of Vaud

  • Civil Engineer

    INGPHI SA, Lausanne

  • Consulting Architect

    B + W Architectes SA, Lausanne

  • Provided Services

    Competition (Winning Project)
    Detailed design
    Supervision of Construction Works

  • Technical Characteristics

    Length: 351.60 m
    Maximum Span: 34.80 m

  • Period

    2005 - 2012

  • Construction Company

    Marti Construction SA, Lausanne
    Freyssinet SA, Moudon
    Coray Construction SA, Muralto

  • Geotechnical

    De Cérenville Géotechnique SA, Écublens


No news linked to this project.

Project Team

  • Claude Broquet-INGPHI



    Manager - Project Manager - Civil Engineer

  • jonathan-krebs-equipe-ingphi



    Associate - Project Manager - Civil Engineer

  • ninh-tran-equipe-ingphi



    Associate - Internship supervisor - BIM Manager & Draftsman and builder

  • Philippe Menétrey-INGPHI



    Manager - Project Manager - Civil Engineer

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