In high-strength steel structures, local plate buckling is a critical concern due to the slenderness of plate elements. This study experimentally and numerically investigated the local buckling analysis of Q550 high-strength steel stiffened plates with T-ribs under compression. Five specimens with different base-plate slenderness were fabricated and subjected to uniaxial compression loading tests. The base plate of all specimens exhibited significant local out-of-plane deformation, and the T-ribs experienced varying degrees of in-plane and out-of-plane deformations. The buckling strength of the specimens decreases with increasing base-plate slenderness. The residual stresses and initial geometric imperfections of the high-strength steel stiffened plate were experimentally measured. Finite element (FE) models incorporating the residual stresses and initial geometric imperfections were established to simulate the buckling behavior of the stiffened plates. The FE models were validated against the experimental results and a parametric study was further conducted. The numerical results indicate that both residual stresses and initial geometric imperfections have a moderate influence on the buckling strength. Furthermore, the formulations in several national design codes used to account for local buckling effects were evaluated. The Eurocode provides approximate predictions, while the Chinese code and Japanese code provide conservative estimations.
Chen et al. (Mon,) studied this question.