Abstract: A device for protecting a mobile or static structure against the blast from an explosion or detonation and associated projections of material. The device includes a protective casing made of several materials, the protective casing being located at a distance from the structure to be protected and connected to the structure by an elastomer connection. The protective casing is elastically deformable so as to be able to deform elastically for the duration of the stress by oscillating to spread the energy of the blast from the explosion over its surface and over time in several directions, and then to return completely or partially to its original shape after a period of time.