TY  - EJOU
AU  - Li, Zhaoqi 
AU  - Liu, Xuan 
AU  - Zhao, Hengkong 
AU  - Zhang, Zhen 
AU  - Li, Yan 

TI  - Simulation of Tensile Progressive Damage in Thick Ply-Drop Composites with Open Holes
T2  - The International Conference on Computational \& Experimental Engineering and Sciences

PY  - 2025
VL  - 33
IS  - 4
SN  - 1933-2815

AB  - The growing use of ultra-thick composite laminates in aerospace structures demands a deeper understanding of their unique damage mechanisms under tensile loading, which differ significantly from those of thin laminates. This study introduces a novel 3D progressive damage model combining solid elements, the LaRC05 3D failure criterion (enhanced with through-thickness in-situ strengthening effects), and a mixed-mode cohesive zone model (CZM) to predict interlaminar delamination. The model captures the interaction between in-plane damage and through-thickness failure modes in open-hole ultra-thick composites, and addresses stress redistribution, localized buckling, delamination migration, and in-situ strength enhancement. Mesh sensitivity analysis validates the robustness of the model under refined meshing near stress-concentrated regions. A quantitative linkage is established between stacking sequences, interlaminar normal/shear stresses, and delamination initiation, revealing that reduced interlaminar normal strength triggers early delamination and compressive strength degradation by up to 11%. The results highlight that thicker laminates exhibit pronounced "in-situ" strengthening effects and stress heterogeneity, leading to 0° ply micro-buckling near outer layers and 45° ply fiber fracture propagation. Furthermore, matrix cracks accelerate delamination depending on ply orientation, emphasizing the critical role of damage interaction in ultra-thick composites. This work provides a validated numerical tool for optimizing aerospace composite designs against progressive failure.
KW  - Ultra-thick composites; open-hole tensile failure; LARC05 failure criterion; cohesive zone model; delamination interaction

DO  - 10.32604/icces.2025.012239