Colloquium: Sree Harsha Singaladevi (ASM)

Fibre-reinforced composites are increasingly used in aircraft structures due to their lighter weight and tailorable properties. However, certifying these materials requires extensive mechanical testing, highlighting the need for virtual frameworks to predict trans-laminar failure and enhance damage-tolerant design. This thesis introduces a global-local modeling approach to analyze trans-laminar damage growth in notched laminates, facilitating large-scale analysis with reduced computational demands. This research investigates progressive failure in notched laminates, focusing on damage growth and arrest in tapered transition regions. A multi-fidelity approach, using both flat and tapered laminates with consistent ply orientations, enables direct failure comparisons. The methodology includes a low-fidelity model with cohesive elements for crack growth and a high-fidelity ply-by-ply model comparing a user-defined continuum damage model (VUMAT) and ABAQUS’s built-in Hashin model. Results show low-fidelity models align well with high-fidelity models and experimental data, while VUMAT outperforms Hashin in accuracy. Overall, the global-local approach demonstrates reliability and scalability for larger structures, highlighting fibre-aligned meshing and cohesive zone modeling as crucial for damage prediction.

Supervisor: Dr. Boyang Chen