A structural turbine engine casing is disclosed. The casing includes a central hub, at least one intermediate shroud, and an external ring, which are concentric, the external ring and the intermediate shroud being connected via links, the intermediate shroud and the central hub being connected by a series of radially fastened hollow arms. The series of arms includes at least one main arm and at least one secondary arm, each main arm being arranged in the continuation of a link and having a mass which is greater than that of a secondary arm arranged at a distance from the links.