A strain gradient strategy to quantifying longitudinal compression behavior in slender fibrous assembly structures

Abstract

Slender fibrous assembled structures can easily buckle under longitudinal compressive load. The limitation in characterizing the longitudinal compression behavior poses a significant challenge to the mechanics optimization of such structures. To address this challenge, we use one-dimensional yarns as a model system, and the yarns are deformed in bending to form a strain gradient, from tension to compression, along the radial direction of the yarns. The compression modulus as a function of compression strain is calculated based on bi-moduli elastic theory. The evolution of the fiber arrangement and the position of the neutral layer in the yarn is interpreted along with the change of compression modulus. Also, the local stress distribution in the bent yarn was determined by finite element simulation, and it is remarked that the bending property of yarns is sensitive to the compression modulus. The present study offers insights on the modeling and simulation of fabrics and garments in drape and bending deformation. Results from such investigations can provide effective guidance for the mechanical and structural design of textiles and textile-based composites.