The innovative stacked-shell modeling approach is investigated in the frame of an explicit finite element method for the prediction of laminated structural elements' static response, focusing on the interlaminar stress calculation. The main advantage of the investigated stacked-shell modeling technique is the lower computational cost compared to conventional methods, for the same accuracy in displacement and stress results. A laminated plate under sinusoidally distributed transverse loading, a laminated strip under three-point bending and a laminated cylindrical shell under cylindrical bending have been used in the assessment of the developed methodology; static results referring to displacement and both in-plane and out-of-plane stresses of the investigated cases have shown that the proposed technique is highly efficient in the calculation of interlaminar stresses of composite structures, which provides the background for an accurate and efficient delamination prediction.

One of the most important events during an aircraft's service life is the impact of a bird (ie, bird strike), which could possibly lead to catastrophic failure. According to airworthiness authorities, compliance of an aircraft structure to bird‐strike certification specifications can potentially be proved by simulation. In the present work, combined experimental and numerical investigations are performed, aiming to provide a validated numerical simulation tool for the certification of a composite leading edge structure. To increase the numerical simulation efficiency, the stacked shell approach in the frame of the finite element method is adopted. Comparison of numerical and experimental results shows that the proposed methodology is very promising for the simulation of impact events on complex composite structures. The proposed methodology has been applied for the development of a numerical tool for the simulation of bird strike on a composite leading edge structure.

Abstract. The prediction of composite laminate behavior when subjected to low velocity im

The stacked thick-shell modelling approach is investigated in the frame of explicit dynamics FE method for the simulation of composite structures. The methodology is developed for static and dynamic loading conditions and demonstrated in the case of three-point bending of laminated strips. For the validation of the stacked thick-shell modelling approach, experimental testing using laminated short beam shear coupons of the AS4/8552 composite material system is performed and the interlaminar shear strength under impact loading is determined. The specimen dynamic tests were performed using a drop tower apparatus and a specially designed three-point loading fixture. In parallel, conventional three-dimensional solid models are also analysed for comparison purposes. Test results correlate well to the respective numerical predictions, demonstrating the accuracy of the stacked thick-shell approach and the efficiency it provides in interlaminar stresses prediction, which makes the proposed approach suitable for large-scale composite structures simulation, with emphasis in delamination damage propagation.

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