Empirical formula for predicting ultimate strength of stiffened panel of ship structure under combined longitudinal compression and lateral loads

The influence of lateral pressure and stiffener type on the collapse behaviours of steel stiffened panels are investigated in the FE (finite element) analysis. Based on the numerical results, the empirical expressions are derived for the ultimate strength assessment of stiffened panels under combined in-plane axial compression and different levels of lateral pressure. The regression formulae only include the plate slenderness ratio and column (stiffener) slenderness ratio. Hence, to consider the influence of stiffener type, the databases of sample points are separately grouped for various cross sections in the regression process. At the same time, for the convenient of utilizing the regression model, the coefficients are expressed as water head in meters. To investigate the approximating accuracy of regression model, the statistical measurement analyses are conducted by comparing with FE analysis, simplified analytical method and experiments.