On the resistance to penetration of stiffened plates, Part II: Numerical analysis

A series of indentation tests have been carried out quasi-statically on various configurations of stiffened panels. These represent hull plates in ships subjected to grounding or collision actions. The results of the scaled down tests are reported in the first part of this two-part companion paper. This part (II) presents results from numerical analyses with focus on fracture prediction. The performance of two failure criteria is investigated. These are implemented into the explicit finite element code LS-DYNA and are referred to as the BWH instability criterion and the RTCL damage criterion, respectively. In addition, the influence of the element size with respect to onset of failure is studied. Although the study is aimed towards accidental scenarios considering collision and grounding of ships, the investigation also apply to other types of problems. This may for instance be the response of deck structures which are hit by dropped objects, or the response of stiffened panels subjected to explosions or ice actions.