A space-time upscaling technique for modeling high-cycle fatigue-damage of short-fiber reinforced composites

Characterizing short-fiber reinforced polymers under high-cycle fatigue loading is a tedious experimental task. To reduce the necessary experiments to a minimum, we introduce a computational strategy involving a mean-stress dependent fatigue-damage model for the stiffness degradation in short-fiber reinforced polymers. The key challenge in these materials is their inherent anisotropy which makes the necessary mechanical characterization process rather time-intensive, in particular for long-time experiments required for fatigue tests. Computational multiscale approaches may reduce the necessary mechanical tests to a bare minimum, offering significant savings in expense.