Modeling and mesoscopic damage constitutive relation of brittle short-fiber-reinforced composites

摘要

Aimed at brittle composites reinforced by randomly distributed short-fibers with a relatively large aspect ra- tio, stiffness modulus and strength, a mesoscopic material model was proposed. Based on the statistical description, damage mechanisms, damage-induced anisotropy, damage rate effect and stress redistribution, the constitutive relation were derived. By taking glass fiber reinforced polypropylene polymers as an example, the effect of initial orientation dis- tribution of fibers, damage-induced reinforced anisotropy, and damage-rate effect on macro-behaviors of composites were quantita- tively analyzed. The theoretical predictions compared favorably with the experimenta; results.