ABSTRACT
This paper presents experiments and finite element simulations of an unstiffened plate and a stiffened plate quasi-statically punched by a hemispherical indenter, in order to evaluate the penetration resistance of the aluminium-alloy structures in collision and grounding accidents. The results are presented in terms of force-displacement responses and failure modes. In the experiments, the penetration resistance of the stiffened plate is almost twice as large as the one of the unstiffened plate before fracture and these two plates suffer different fracture patterns. In the simulations, the change of the material parameters caused by the welding is considered. The numerical results illustrate that the welded heat-affected zone has a significant effect on the plastic deformation and fracture of aluminium-alloy structures.
