Interacting Damage Mechanisms in Laminated Composites Subjected to High Amplitude Fatigue

This manuscript provides a combined computational-experimental investigation of the interaction of damage mechanisms in carbon fiber–reinforced polymer (CFRP) laminated composites subjected to fatigue loading. The investigations particularly focus on ${[60,0,-60]}_{\mathrm{3S}}$ laminates, whose behavior demonstrates strong interactions between the relevant damage modes. Numerical investigations are performed using a spatiotemporal computational homogenization-based multiscale life prediction model. The computational approach relies on a model order reduction methodology to develop a meso model that can capture the relevant failure mechanisms in a computationally efficient manner. The model was calibrated using a suite of experimental data from the static and fatigue response of simple laminates made of the same constituents. The calibrated model along with experimental observations from acoustic emission and X-ray computed tomography were employed to understand the relative roles of delamination and splitting and their interactions in controlling fatigue failure processes in CFRPs.