Fracture propagation in composites with biaxial fiber reinforcement

Fracture characteristics such as damage progression, work of fracture, ultimate fracture loads. and failure modes are evaluated by computational simulation for composites with biaxial braided fiber reinforcements. Several Graphite-Epoxy Mode I compact tension (C(T)) specimens with different biaxial fiber orientations are modeled and simulated. Damage initiation, growth, and propagation processes at the microscopic level are tracked, enabling a more insightful interpretation of the test results. The effects of ply-layup with various orientations of the braid axis with reference to the notch directions are investigated with respect to their influences on damage and fracture progression characteristics. Results validate the computational simulation method and identify fracture characteristics for biaxially reinforced composites.