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The purpose of this paper is to improve knowledge of the water impact phenomenon from both the experimental and numerical points of view.

A drop test campaign on water was carried out on semi‐cylindrical steel structures. Therefore, an experimental database for validation purpose was generated. Subsequently, a finite element model was developed in LS‐DYNA in order to reproduce the tests. The behaviour of water was modeled by using the smoothed particle hydrodynamics (SPH) methods. Numerical simulations were compared to experimental data and the influence of some numerical parameters on the simulations was investigated.

The FE model was found to be able to reproduce the tests, at least in terms of acceleration peak and distribution of plastic deformation. Acceptable prediction was also found for the pressure peak in soft areas.

In case of low velocity impact, the water model was found to be too rigid and the acceleration peaks were over‐predicted by the simulations. Further investigations are needed to adjust the water model in order to obtain better results also in the case of low velocity impact.

The experimental database could be very useful to the crashworthiness community to validate their numerical models. Moreover, the present paper provides guidelines to modelling the water impact correctly.

This paper's aim is to focus on the design, manufacture and test of a stiffened panel in composite material with integrated longitudinal foam‐filled stiffeners, spar and rib caps, using one‐shot liquid infusion (LI) process, reducing weight and number of subparts respect to metallic reference baseline P180 Avanti vertical fin.

Extensive activities in computational applications in order to improve the efficiency of the design process finite element analysis/structural sizing codes have led to an optimised engineering design process that resulted in a successful stiffened carbon fibre reinforced polymer panel design in terms of weight and number of parts with respect to the metallic baseline.

The composite panel has fulfilled all the design requirements (reduction of mass and number of parts with respect to the metallic reference baseline) overcoming the certification static test, and confirming the reliability of the theoretical analyses.

The composite aircraft components, conceived as unitized structure by one‐shot process, guarantee not only a mass reduction, compared to aluminium components, but assure also the reduction of the number of subparts and of the assembly process cycle time. On the other hand, the LI technology implies the development of more specific and advanced techniques to control the manufacturing and the weight.

The stiffened panel is the most used component in the aircraft structures; the solution shown in this work can find applications in many parts of an aircraft.

The results obtained in this work can be useful to those who work in aeronautical structural departments with the aim to reduce weight and subparts of the airframe.

The main objective of this work is to assess the current capabilities of different commercial finite element (FE) codes in simulating the progressive damage of composite structures under quasi-static loading condition in post-buckling regime.

Progressive failure analysis (PFA) methodologies, available in the investigated FE codes, were applied to a simple test case extracted from literature consisting in a holed composite plate loaded in compression.

Results of the simulations are significantly affected by the characteristic parameters needed to feed the degradation models implemented in each code. Such parameters, which often do not have a physical meaning, have to be necessarily set upon fitting activity with an experimental database at coupon level. Concerning the test case, all the codes were found able to capture the buckling load and the failure load with a good accuracy.

This paper would to give an insight into the PFA capabilities of different FE codes, providing the guidelines for setting the degradation model parameters which are of major interest.