Characterization of Low-Velocity Impact Damage in Asymmetric Composite Shells

Based on numerical modelling, this study investigates asymmetric semicylindrical composite laminate shells' damage characteristics under low-velocity impact loads. For this purpose, several asymmetric stacking sequences were subjected to low-velocity impact and the results were analysed in terms of force, displacement, contact time, and absorbed energy. It is concluded that the maximum impact force decreases with an increase in the number of layers oriented at 0°, particularly in the upper half of the laminate. The laminates with a 45° orientation in the upper layers present the lowest displacement values, whereas the laminates with the upper layers oriented at 0° exhibit longer contact times. It is also observed that intralaminar damage is responsible for almost half of the total impact energy, followed by delaminations and friction. Stacking sequences with upper layers at 45° exhibit slightly higher energy dissipation due to intralaminar damage (fibre failure) and interlaminar damage (delamination).