Empirical formulae assessment of ultimate strength for perforated stiffened panels under longitudinal compression

The present paper studies the influence of cut-outs of local plates on the ultimate strength of stiffened panels based on the tests and numerical simulations. Four intact and perforated stiffened panels subjected to uniaxial compression loads were tested firstly. The initial imperfections of the specimens have been measured before testing, which were used in the FE (finite element) analysis. The tensile tests are used to determine the properties of material. The experimental results are used to verify the modelling technology of FE models. Based on the numerical simulations, the parametric studies with various configurations including the initial twisting distor-tion, boundary condition and the dimensions of opening are performed to investigate their influences on the collapse behaviours of the stiffened panels. It is found that the residual ultimate strength of perforated stiffened panel mainly depends on the transverse length of opening. Using numerical database, the empirical formulae of ultimate strength of perforated stiffened are developed.