Investigations on deflection effect of a Z-shaped grillage subjected to an obliquely penetrating ogive-nose projectile

Deflection could occur when the projectile obliquely penetrates multi-cabin structure of the ship, and that could bring great uncertainty to the damage resulted from internal-blast. According to the structural characteristics of 3000 tonnage ships, a Z-shaped grillage which could better reflect the actual oblique penetration situation was proposed in this paper. Then a series of simulations of an ogive-nose projectile obliquely penetrating the Z-shaped grillage were implemented, in which the material parameters from references were further validated by the large-scale penetration experiments. Based on the numerical results, the deflection modes relating to structural deformation and failure were revealed, and the effects of initial velocity and impact position relative to the T-bar on deflection were discussed. Finally, a deflection quantification map was given. Significantly, the deflection of projectile did not necessarily decrease with the initial velocity increasing on Top-view, and the deflection exhibited high sensitivity to the impact position relative to the T-bar within a certain region on Side-view.