Numerical and analytical study of the stiffener effects on the structural resistance of a plate cut by a wedge

Stiffened panels are widely used in ship and offshore structures and the evaluation of cutting resistance is important for structural safety assessment in ship collision and grounding accidents. This paper presented numerical and analytical analyses for cutting analysis stiffened plates. The numerical simulations were firstly validated against experimental data and the stiffener effects on the cutting resistance were then studied through numerical simulations by changing the stiffener direction and thickness. The longitudinal stiffener was found to influence the resistance from an earlier stage while a much larger peak value of cutting resistance was reached for transversely stiffened plate. Based on the numerical study and review of previous formulas, a new analytical model was proposed to predict the cutting resistance of stiffened plates. The new method established analytical model for longitudinal and transverse stiffeners respectively to capture their dynamic responses, and the coupling effects from them were considered by dynamically updating the curling radius of plate during cutting process. The newly developed method was validated and verified against existing experimental data and the presented numerical results, and very good agreement was achieved. The newly proposed method was also compared with existing formulas to investigate the adaptivity and it is found that the accuracy is better than previous formulas, which combines with equivalent thickness method, especially when predicting the cutting resistance of transversely stiffened plate. The present study can benefit the structural damage assessment of stiffened decks or bottom plates of ships in real collision and grounding accidents.