This paper presents the work on six single-stringer specimens manufactured using the card-sliding technique with non-crimp fabrics and adopting a Double-Double (DD) stacking sequence. These specimens, representative of sub-structure level components, are used to investigate post-buckling and failure in aerospace structures. Two specimens maintain a constant thickness cross-section, while four are tapered, two of which incorporate a Teflon insert in the stringer flange. All specimens are tested under compression loading conditions, inducing skin buckling, skin-stringer separation, and eventual collapse. Numerical simulations are validated by experimental results and serve to analyze the specimens behavior and the failure mode. The load versus displacement curves of both experimental tests and Finite Element Method (FEM) analyses are compared, along with the out-of-plane displacement field. Subsequently, the observed failure modes are discussed, focusing on the various mechanisms that occurred and considering the impact of flanges and stiffener tapering. Both the FEM simulations and experimental tests demonstrate good agreement, with the flanges tapering revealing notable results. This offers promising evidence of a viable solution to optimize aeronautical structures and enhance resistance to skin-stringer separation.

Ice impact is quite common and may become critical especially if it involves the transportation sector. Simulation tools may help in the structural design phase to increase the ability to withstand this kind of impact and/or to analyse the effect under extreme weather conditions. Such tools require an accurate description of the mechanical behaviour and therefore a detailed investigation about the dynamic mechanical properties of ice is of great interest. In the present work, material characterizations of ice, including tensile and compressive tests, were carried out under different strain rates. Two different material models (i.e., the modified Johnson-Cook model and Johnson-Holmquist II model) were calibrated. Then, impact tests using ice as a projectile with aluminium panels as a target were conducted to validate the material models of ice under impact loading. Furthermore, the replication effect of ice projectiles was investigated under different impact energies based on the mechanical responses and damage phenomena of ice for both models. Results showed that while both models are able to provide reliable predictions of the impact behaviour of ice projectiles, the Johnson-Holmquist II model presents a better performance as impact energy increases.