Experimental and numerical studies on the dynamic response of stiffened plates under confined blast loads

Abstract Stiffened plate widely exists in ships, steel girders and wing of airplanes for its good bending resistance and lighter weight. The main purpose of this work is to investigate the dynamic response of stiffened plate subjected to confined blast loading through both experimental and numerical approaches. Firstly, several field blast experiments of box-shaped specimens with different dimensions and different explosive weight were conducted. The damage features of both inner-stiffened and outer-stiffened plate were obtained and investigated. Then, numerical models were built and validated by the experimental results, and the dynamic response processes were analyzed. Both the experimental and numerical results show that outward deformations produced in both inner-stiffened and outer-stiffened plate, while the ultimate deflection of outer-stiffened plate is smaller than that of inner-stiffened. In the meantime, overall bending deformations are observed in the outer stiffeners, while in-plane bulking of the flanges and instability failure of the web are observed in the inner stiffeners. In addition, the different dynamic response of stiffened plate under confined and unconfined blast loading were analyzed and compared using the validated numerical method, and the tendency of the dimensionless deflection of inner and outer stiffened plates subjected to confined blast were discussed.