Structural resistance of lightweight stiffened panels submitted to buckling

Abstract

Abstract The primary goal of the study herein presented was to evaluate the remaining strength of a stiffened panel belonging to a ship’s deck that suffered some deformations during service. For this purpose, some representative panels of the ship were modelled, aiming to simulate a range of typical deformations, from the ones found on board, as is, through to some extreme cases of deformations that could lead to structural collapse. After shaping the stiffened panels, compressive in-plane loading was applied, simulating longitudinal bending of the hull in a sagging condition. Non-linear structural analyses were carried out using the Finite Element Method (FEM) and ANSYS software. It was found that the existence of large deformations between reinforcements led to the loss of strength of the original stiffened panel and the local deformations occurring near the reinforcements do not affect the strength of the panel significantly. The case with a higher loss of strength was the one relative to the collapse of a longitudinal reinforcement profile of the deck panel. In addition, the main types of buckling found in the panel were the local buckling of plating between stiffeners and the lateral-torsional buckling of the smaller stiffeners. Despite the moderate loss of strength found on some of the stiffened panel studied, it was possible to conclude that this loss of strength does not compromise the normal safe operation of the ship, even in extreme load.