Abstract: A structural fabric (20, 28, 40, 48) and a method for making the same is disclosed. Structural fabric (20) is comprised of a plurality of substantially parallel, uniaxial structural yarn (22) and a secondary yarn (24) for holding the structural yarns (22) in place. The structural yarns (22) are oriented at an angle skewed from both the fabric centerline (26) and a line perpendicular to the fabric centerline (26).A double biased fabric (28) is made by sewing two fabrics (20) together with secondary yarn (39). An alternate double bias fabric (40) is made by sewing together with secondary yarn (46) the two layers of a flattened helix made from structural yarn (42, 44) running spirally substantially the length of the fabric (40).A triaxial fabric (48) is made by sewing together with a secondary yarn (56) two single biased fabrics (50, 52) and a layer of longitudinally-extending structural yarn pieces (54).

Abstract: Non-woven, multi-layer biased structural fabric is disclosed, which is comprised of at least three layers of parallel structural fibers, with no secondary yarns or fibers in the plane of the layers to hold said fibers in parallel relationship. Both the vertical relationship of the layers and the parallelity of the fibers within each layer is maintained by vertical stitching. The fabric may be made into a structural composite by saturation and subsequent curing with a curable, crosslinking resin. An apparatus and method for forming that fabric and composite is also disclosed, which is comprised of aligned weft lay down carriages arranged sequentially and further aligned with a stitching machine. A means for advancing the fibers from each weft lay down carriage into the stitching machine passes along the weft carriages. As each layer is laid down on top of the previous layer, it is engaged by the advancing means and so brought into the stitching machine, where the layers are vertically stitched through.

Abstract: Non-woven, multi-layer biased structural fabric is disclosed, which is comprised of at least three layers of parallel structural fibers, with no secondary yarns or fibers in the plane of the layers to hold said fibers in parallel relationship. Both the vertical relationship of the layers and the parallelity of the fibers within each layer is maintained by vertical stitching. The fabric may be made into a structural composite by saturation and subsequent curing with a curable, crosslinking resin. An apparatus and method for forming that fabric and composite is also disclosed, which is comprised of aligned weft lay down carriages arranged sequentially and further aligned with a stitching machine. A means for advancing the fibers from each weft lay down carriage into the stitching machine passes along the weft carriages. As each layer is laid down on top of the previous layer, it is engaged by the advancing means and so brought into the stitching machine, where the layers are vertically stitched through.