Mathematical Modeling of the In-Plane Shear Behavior of Dry Thick Non-Crimp Stitched Textile Reinforcements

Abstract

A novel dry, thick, non-crimp stitched textile reinforcement was developed at the University of Ottawa’s Preforming Technology Laboratory to satisfy the growing demand for thick textile reinforcements in aerospace manufacturing applications. Previous experimental investigations examined the influence of stitch orientations (R-45, R+45, R0, and R90) on the in-plane shear behavior of the reinforcement. Among these orientations, the R-45 and R+45 configurations demonstrated superior shearability. The present study develops a mathematical model to simulate the in-plane shear response of the reinforcement using MATLAB. The proposed model provides an efficient alternative to extensive experimental testing, which is both time-consuming and costly. Experimental data obtained from articulated-frame shear tests were fitted using polynomial regression techniques. Different polynomial orders were evaluated using numerical and graphical fitting criteria to determine the optimal model complexity. The results showed excellent agreement between the simulated and experimental responses for both R-45 and R+45 stitch orientations, thereby validating the effectiveness of the proposed modeling approach. The developed generalized mathematical model provides a reliable and computationally efficient tool for predicting the in-plane shear behavior of thick stitched textile reinforcements.