Opening of the new railway line Geneva - Annemasse
On the 15th of December 2019, trains ran via "CEVA" - the new route from the Swiss railway station Geneva-Cornavin via Geneva-Eaux-Vives to Annemasse in France for the first time after eight years of construction. Almost one million residents in Switzerland and France will benefit from CEVA and the associated expansion of the "Léman Express" rail network. Gruner and Stucky employees made a considerable contribution to the success of the project. The CEVA project itself comprised the construction of an 8.8km long, double-track, mostly underground line and the extension of the existing facilities over 7.3km. Five stations were built according to a concept by Atelier Jean Nouvel as well as 2 excavated tunnels and several cut and cover sections. The construction of this facility in the densely urban area with many settlement sensitive buildings and partly through very compressible subsoil layers was extremely demanding.
Stucky's engineering team worked as part of the GECA consortium on this challenging project for 15 years. The GECA consortium led tunnel Champel, which covered the 1 631m section between Val d'Arve and Geneva Eaux-Vives station, including the Champel-Hôpital stop. The Stucky team was involved in all design and construction phases, from the preparation of solution variants to the elaboration of as-built drawings. In addition, the role of the engineers evolved constantly during the project phases: for the Champel-Hôpital station, we worked on the possible construction solutions using numerical modelling and supported preparations for the bidding documents as well as managing and supervising the day-to-day construction.
Gruner’s geotechnical engineering specialists were responsible for the test engineering mandate for the five railway stations, the cut and cover sections and the two excavated tunnels. They verified the design basis and hydrogeology, they also verified the construction method as well as performing the static calculations. In addition, Gruner prepared comparative calculations, including various settlement and deformation forecasts for the supporting structure, the subsoil and the existing structure (using 3D finite element analysis). The underground railway stations of the CEVA project were mostly constructed using the cut and cover construction method. Depending on the geology, the tunnels were excavated partly in a full excavation cross-section with local face protection and partly in partial cross-sections. Thanks to the various anticipatory measures, it was possible to excavate under many sensitive and old buildings without damaging them at all.
For more information: https://www.gruner.ch/en/references/bahnverbindung-ceva-genf