Damage Tolerance of Notched Composite Laminates with Reinforcing Strips

An investigation was performed to study the effects of reinforcing strips on the notch strength and failure response of laminated composites. A three-dimensional finite element method 3DPDCOM which combined the commercial ABAQUS code with a progressive failure analysis was developed for the study. Composite specimens containing a cutout with or without unidirectional reinforcing strips were tested to verify the model predictions. The test data and numerical simulations proved to be in agreement with each other. Results showed that the notch strength and damage progression of composite laminates could be affected significantly by adding reinforcing strips in front of notches such as crack tips and cutouts. The change in notch strength strongly depended upon the geometry, properties, and bond strength of the reinforcing strips. The strips could significantly alter the failure progression and failure modes in composite plates.