The influence of fabric structure on the static and dynamic compressional performance of weft-knitted spacer fabrics

Abstract

Spacer fabric is a type of 3D textile characterized by the presence of two distinct fabric layers that are interconnected by spacer yarns. This investigation focused on analyzing the impact of the weft-knitted spacer fabrics’ thickness resulting from different spacer layers’ knit patterns on the compressional behavior of the spacer fabrics designed specifically for shoe soles. In this regard, the static and dynamic compressional behavior of spacer fabrics was examined according to the simulation carried out for walking. The results obtained from the application of static compressive force on spacer fabrics revealed that by increasing the spacer yarn’s length, the compression and recovery energy, dissipated compression energy, relative compressibility, and thickness recovery of spacer fabrics decreased; in contrast, the surface thickness changes increased. In addition, by examining the results of dynamic compressibility, it was observed that after the first loading cycle, the mechanical properties of spacer fabrics have changed significantly; however, with the increase in the number of loading cycles, the variation rate of these properties has decreased and reached a constant value. Also, with the increase of loading cycles, compressibility, and recovery work, dissipated compression energy and the elastic strain decreased, while the residual strain and ratcheting strain increased. Finally, an analysis of the compressional behavior of weft-knitted spacer fabrics based on viscoelastic models showed that the three-component model with a nonlinear spring can successfully correlate with the experimental results.