Composite Structures, cilt.312, 2023 (SCI-Expanded)
In this study, dynamic delamination behavior in asymmetric GFRP tapered laminates under quasi-static tensile loading is investigated experimentally and numerically. Abaqus/Explicit cohesive interface modeling is utilized to simulate delamination initiation and dynamic propagation. Time-frame based delamination mechanisms predicted in simulations are compared to in-situ high-speed camera images for four geometrically asymmetric specimens containing grouped and ungrouped drop-off types. It is observed that the ply drop-off type governs not only the strength of the tapered beam but also the delamination progression path and its stability. For specimens with consecutive drop-offs, a good agreement is obtained between the experimental observations and numerical results in terms of delamination onset location, propagation patterns, and instability of delamination growth. For specimens with ungrouped drop-offs, a modified cohesive strength approach is shown to be necessary to enhance the aforementioned correlations. The effect of such modification on delamination propagation manner is explicitly shown for the first time in this paper.