A finite element simulation of the test procedure of stiffened panels

Abstract The Canadian Forces (CF) and the US Interagency Ship Structure Committee (SSC) jointly sponsored a full-scale testing project to study the load-carrying characteristics of single stiffened panels under different load combinations and with various types of damage. A full-scale testing system was designed and constructed, in which the stiffened panel was simply supported by cylindrical bearings at both ends and restrained by discrete carriages along the sides to simulate the boundary conditions resulting from a grillage environment in ship hull structures. Twelve full-scale panels, including seven “as-built”, two “dented” and three “corroded” specimens, were tested in this set-up. In the meantime, a series of nonlinear finite element analyses were conducted to simulate the test procedure and predict the collapse loads and buckling behavior of these stiffened panels. The finite element models were established by a direct mapping of measured imperfections to nodal points. Residual stresses were introduced using a thermal stress analysis procedure. For models with spatial discontinuities, locally refined meshes and the branch shifting technique were used to achieve the desired failure modes. In this paper, the finite element solutions are presented in detail and compared with the test observations. The good agreement between the experimental and numerical results indicates that the nonlinear finite element method is capable of predicting plastic post-buckling behavior of stiffened panel structures.