Onset of Strain Localization in Fiber Reinforced Composites Subjected to Plane Stress Loading

Abstract

The main objective of this study was to find analytical solutions for the onset of strain localization in fiber reinforced composites subjected to plane stress loading. In particular, elastic multidirectional fibers are embedded into an elastic-plastic matrix. A macroscopic tangent stiffness tensor of the fiber-reinforced composite is obtained by consistently homogenizing the contribution of fibers in a cylindrical representative volume element. Upon deriving analytical solutions their properties are further illustrated on the example of Drucker–Prager model. Results show that fibers decrease the critical hardening modulus, thus inhibiting the onset of strain localization. The main fiber parameters that control the stress level at the inception of strain localization are their volumetric content and their stiffness modulus.