An analytical model for the in-plane elastic shear modulus of plain-woven fabric composites and its application and experimental validation

In this paper, a new analytical model is proposed that employs experimental data as input to predict the in-plane shear modulus of plain-woven fabric composites. This model boasts high efficiency and rapid computation. Initially, the composite yarn is considered as an idealized curved beam, with its undulation path described by an arc curve and its cross-section simplified into a lenticular shape. Subsequently, a force analysis of the yarn segment is conducted, and the results of the analytical model are derived using the minimum potential energy principle and Castigliano’s second theorem. The input parameters for the analytical model are obtained through thermal ablation experiments and microscopic observations, with T300/Cycom970 plain-woven fabric composites selected as the experimental subject. In addition, tensile tests on ±45° laminates are conducted to validate the effectiveness of the analytical model. The results demonstrate a minimal deviation of −4.15% between the experimental outcomes and the predictions of the analytical model, thereby verifying the model’s validity and the accuracy of the experimental parameters. Leveraging the validated model, the study investigates the influence of crimp ratio and fiber volume fraction on the in-plane shear modulus. Furthermore, to enhance the applicability of the model, a simplified improvement scheme that incorporates temperature and humidity considerations is proposed. This model not only effectively addresses the mechanical property analysis challenges of plain-woven fabric composites, but also provides valuable references for parameter estimation, model construction and experimental design of other woven composite materials.