Prediction of Poisson’s ratio of worsted woven fabrics considering fabric extension in various directions

Abstract

The paper aims to analyse the Poisson’s ratio of woven fabrics in terms of fabric tensile behavior in different directions. In this research, measurement of the Poisson’s ratio of a series of worsted woven fabrics has been carried out through uniaxial extension of the fabrics on the tensile testing machine and tracing the dimensional changes of them during the load application. By the use of the Matlab curve fitting toolbox, the best equation for representing the relationship between the Poisson’s ratio and the tensile load exerted to the fabric is derived. The mentioned function can be utilized for the prediction of the Poisson’s ratio at various levels of load. Due to the non-isotropic behaviour of the woven fabrics, the differences of the Poisson’s ratio obtained in the two main fabric directions (warp and weft) are investigated. Finally, the influence of weave structure and weft density on the Poisson’s ratio of the fabrics is studied. Analysis of the results reveals that the value of the Poisson’s ratio in terms of tensile load follows a similar trend for all the fabrics in both warp and weft directions. The mentioned trend is fitted reliably by a trigonometric function with the correlation factor (R²) of more than 92%. The result of investigating the Poisson’s ratio in two perpendicular directions is found in agreement with the structural changes of the fabric in different directions. Statistical analysis of results confirms that the effect of weave structure and weft density on the Poisson’s ratio is significant at the 95% confidence level.