Computational Investigation of the 3-D effects on Dynamic Fracture of Curved Composite Laminates

Tamer Tahir, Ata
Çöker, Demirkan
Composite materials are used more and more in aerospace, commercial and industrial applications due to high specific stiffness, strength and damage tolerance capability. The main advantage of composite materials, it allows the stiffness and strength of the material to change with direction of loading. Hence tailoring structıres to meet load requirements reduces weight and allows designer to optimize structure. Considering all these advantages, primary and secondary structural elements of recent commercial aircrafts are made of laminated composite materials rather than aluminium alloys. In testing of L-shaped laminated composite parts [1,2], two dominant failure modes (delamination, matrix cracking) are observed which reduce the load carrying capacity of the component eventually leading to collapse of the part. In order to form an understanfing of failure types observed in recent experiments [3,4], computational simulations of the failure of L-shaped composite beams under combined moment/axial loading are carried out. The main aim of this study is to model the failure patterns according to ply sequence and to suggest reinforcement methods to increase durability of these structures. In this study, dynamic delamination under quasi- static loading is studied using implicit/explicit finite element method in conjunction with Cohesive Zone Modelling (CZM). Finite element models are generated using 3-D elements for the defined layup configuration and solutions are performed using Abaqus. The lay-ups are [0]30 and [03 /903 /03/903 /03]s The location of delamination initiation and propagation for these two different layup configurations are investigated numerically. Results verified that the location of delamination initiation is approximately half of the width. Since delamination initiates in half-width of the specimen and propagates to the edge, 2D simulations of delamination and experimental studies observe only edge delamination. Finally, the effect of cohesive element parameters on crack propagation front will be studied.
21th International Conference on Composite Structures


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Citation Formats
A. Tamer Tahir and D. Çöker, “Computational Investigation of the 3-D effects on Dynamic Fracture of Curved Composite Laminates,” presented at the 21th International Conference on Composite Structures, 2018, Accessed: 00, 2021. [Online]. Available: