The construction of large structures (tower, bridge, stadium, museum, etc.) or an architectural building with complex shapes, requires a good knowledge of their behaviour in the face of climatic events. The same applies to civil engineering infrastructure, naval, aerospace, ground transportation, or National Defence equipment. The climate wind tunnel Jules Verne of the CSTB was commissioned in the 1990s. It makes it possible to simulate and analyse the behavior of structures or systems on a scale 1 against sometimes extreme climatic events. This equipment allows the improvement of the design of products (bridge, gondola, TGV, etc.), depending on the weather conditions to which they are subjected. The Jules Verne climate wind tunnel modernisation operation includes the following investments: — works to modify the geometry of the main wind tunnel (dynamic ring) to optimise the aerodynamic field, – installation of new equipment, – expansion of control rooms, preparation halls, – development of numerical simulation capabilities to complement the offer of testing services with virtual simulations. The operation complies with the selection criteria for action 1.1.2 “Support to regional innovation platforms and technological development and innovation tools for business” of the ERDF/ESF 2014-2020 Operational Programme. It fits into p