Internal geometry variability of two woven composites and related variability of the stiffness

In this work, the internal geometry measurements of two woven composites are analyzed: cross section of the yarns, fiber volume fraction, crimp, misalignment of the samples, thickness of the plates, nesting value, and so forth. The chosen textile composites are produced using the same resin reinforcement and same architecture, but have different yarn size (3K and 12K). The dispersion of measured geometrical parameters is introduced in a numerical multiscale modeling approach to evaluate the macroscopic stiffness values. A sensitivity analysis is performed for each geometrical parameter and laminate stiffnesses are derived. These are linked to the experimentally obtained elastic properties by tensile tests. Finally, the unit cell size scale effect for measured geometry variability and experimentally obtained elastic properties are evaluated.