ABSTRACT
The construction of the Cigéo project, future deep geological disposal facility, represents because of its scale, 260 km of underground galleries, a unique case in Civil Engineering. Unlike a classical linear tunnel project, Cigéo is a meshed and complex underground architecture. In this network of underground galleries, many simultaneous excavating faces will have to be deployed while taking into account all the impacts of the different construction sites. Actually, this meshed architecture implies a large number of intersections, requiring the development of a global understanding of the problematics to ensure that the chosen methods are compatible with the flux necessary for each construction site. Thus, the building of the Cigéo project will require all the construction methods of rock tunneling: open shield TBM, deep shafts, conventional drill and blast or hydraulic hammer, and micro-tunneling. This article will focus on the singularity of CIGEO project and the design process based on for the preliminary design stage, to allow optimization and to secure the planning of the project.
