Aeronautical casing preform comprising a fibrous web with two deployable portions

An aeronautical casing fibrous preform comprising a winding of one or more turns of a fibrous web having a strip shape extending in a longitudinal direction over a determined length between a proximal edge and a distal edge, in a lateral direction over a determined width between a first side edge and a second side edge, and in the thickness between an inner face and an outer face,

• the fibrous web having a three-dimensional or multi-layer weave between a plurality of layers of warp yarns or strands extending in the longitudinal direction and a plurality of layers of weft yarns or strands extending in the lateral direction, the fibrous web comprising a distal portion present between an intermediate part and the distal edge in the longitudinal direction,
• the distal portion comprising, in the direction of its thickness, an inner portion and an outer portion, disposed such that the inner portion extends between the inner face and the outer portion, and the outer portion extends between the inner portion and the outer face, wherein the outer portion is connected to the inner portion by at least one linking portion, the outer portion comprising first and second deployable portions extending in the lateral direction from the linking portion over a determined width, the first deployable portion being separated from the inner portion by a first non-interlinked area, the second deployable portion being separated from the inner portion by a second non-interlinked area,
• the inner face of the proximal edge of the web being located on the side of a radially inner face of the preform, and the outer face of the distal edge of the web being located on the side of a radially outer face of the preform.