A corrective function for the estimation of the longitudinal Young's modulus in a developed analytical model for 2.5D woven composites

In this article, the problem that is faced when the developed analytical model is applied to 2.5D interlocks of the 'yarn-yarn' type is discussed. The difficulty encountered is taking into account the influence of the number of weft yarns covered by the warp yarn. Different architectures of these interlocks will have the same stiffness matrix when modeled with the developed analytical model that uses the volume proportion of the three phases: warp, weft, and matrix. The influence of the number of weft yarns on the longitudinal Young's modulus is studied. A corrective function has been evaluated using a finite element numerical modeling of four fictive woven composites created with 'ANSYS' software. These woven composite have the same undulated warp and linear weft yarns, while they differ in the number of weft yarns covered by a warp yarn. The longitudinal Young's modulus is evaluated for each composite using a numerical model which is also presented in this study. Moreover, a cross-ply laminate (0,90) is modeled by the classical laminate theory in the estimation procedure of the corrective function. The corrected longitudinal Young's moduli show better agreement with numerical results compared to noncorrected ones.