Research Information System
AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025, Florida, United States Of America, 6 - 10 January 2025, (Full Text)
Necessary ply termination locations for improved weight and stiffness distribution in laminated composite structures can cause early initiation of delamination due to the elevated interlaminar stresses in wind turbine blades and composite aerospace structures. To improve the performance of such structures, delamination resistance techniques are developed in the literature. However, the effectiveness of the resistance technique can differ depending on the predominant delamination mode and taper angle in the tapered laminate. In this study, recent delamination resistance techniques; tape scarfing technique and nonlinear taper geometry, are investigated numerically, and a design concept effective in resisting both thin section and thick section delamination in ply drop-off locations is proposed. For this purpose, finite element models are created in ABAQUS, and cohesive zone modeling technique is utilized for delamination prediction. Interlaminar stress distributions obtained from the models showed that while tape scarfing is effective in reducing the stresses in the thick side of the ply drop off regions, the nonlinear taper geometry can reduce the stresses in the thin side of the laminate. A delamination resistance technique combining both tape scarfing technique and nonlinear taper geometry is proposed to reduce both thin and thick side stresses in ply drop-off regions.