US Patent 7713893 Three-dimensional woven integrally stiffened panel

An integrally woven three-dimensional preform with stiffeners in two directions constructed from a woven base fabric having first, second and third woven fabrics. A plurality of yarns are interwoven over a region between the first and second fabrics such that the first fabric is foldable relative to the second fabric. An additional plurality of yarns are interwoven over a region between the second and third fabrics such that the third fabric is foldable relative to the second fabric. Upon folding of the woven base fabric, the integrally woven three-dimensional preform with stiffeners in two directions is formed.