Large inelastic deformation resistance of stiffened panels subjected to lateral loading

This paper presents a simplified formulation for the assessment of large deformation resistance of stiffened panels subjected to lateral loading. The method is based on rigid plastic material assumptions and the use of yield functions formulated in terms of stress resultants. The method considers the flexibility of the panel ends with respect to inward motion, while the rotational boundary conditions are free or clamped. Concentrated and distributed loads are considered, as is patch loading. The resistance-deformation curves predicted by the proposed method are compared with results from experiments and using LS-DYNA, and good agreement is obtained for panels that are not dominated by shear failure and tripping or local buckling of stiffeners at the early stage of deformation. The formulation provides a useful tool for quick estimates of panels subjected to abnormal or accidental static and transient lateral loads such as ship collisions, dropped objects, explosions, slamming, hydrostatic pressure and ice actions.