Analysis of bending stiffness reduction in thin woven composites under large curvatures

Abstract

Ultra-thin woven fiber composites are widely used in space structures due to their high weight to strength ratio. However, when subjected to high curvature bending, these composites experience a reduction in bending stiffness, which can hinder their structural performance. This research investigates the underlying mechanisms contributing to this stiffness reduction, focusing on two key factors: nonlinear geometric deformations of the tows and cohesion between tows. A multiscale modeling approach is employed, utilizing a representative unit cell to capture the meso-scale behavior of the woven composite. Analysis of simulation results indicates that nonlinear geometric deformations contribute less significantly to stiffness reduction while the loss of cohesion between tows plays a dominant role.