FIELD: textile, paper.
SUBSTANCE: invention relates to a fibrous preform (100) woven as a single piece using three-dimensional weaving, intended for the shelve manufacture of a composite material with a closed box construction for a turbine engine fan. In each plane of the fiber preform, a plurality of threads are interwoven with the layers of fill yarn threads on the first, second and third sections (102, 104, 106) of the fiber preform; at the same time, there remains a closed (thread) non-interlacing zone 108 separating the first section from the second section over a certain dimension of the fiber preform length in the direction of the base between the upstream (thread) non-interlacing border (108a) and the downstream (thread) non-interlacing border (108b); and at the same time, at least one open (thread) non-interlacing zone (110) that separates the second section from the third section over a certain dimension of the fiber preform length in the direction of the base, from the (thread) non-interlacing border (110a) to the downstream (100c) fiber preform. The invention also provides a method of manufacturing a preform for a composite material shelf with a closed box construction designed for a turbine engine fan using such a fiber preform.
EFFECT: increased effectiveness of the preform.
15 cl, 23 dwg
