AN ANALYTICAL SOLUTION FOR EVALUATING STRUCTURAL RESISTANCE OF A STIFFENED PLATE UNDER LATERAL IMPACT WITH LARGE INDENTATION

Ship collision accidents occur frequently despite the efforts of developing collision-avoidance technology and tools. The structural crashworthiness analysis is thus important and developing rapid prediction tools have been a hot field in the past decades. This paper presented a new analytical solution for assessing the structural resistance of a stiffened plate under lateral impact from a raked bow. Numerical simulations were firstly carried out to help identify the mechanisms of structural deformation of the stiffened plate from the side shell. The damage modes of the stiffened plate were categorized as three types with the continuous indenting of the bow. Multiple analytical formulas were derived to cover the process of damage evolution, including plate denting, plate rupture and plate tearing. Detailed analytical models for stiffeners were also developed for various deformation phases instead of using equivalent thickness method. Finally, an integrated method was developed based on the derived formulas for each single component. The integrated method innovatively considered the coupling effects and interactions between various structural members in the collision analysis by dynamically correcting some parameters. The method was verified against the numerical simulations of full-scale ship collisions through several typical scenarios and good accuracy was achieved. The newly developed method is valuable for crashworthiness design in the preliminary designing phase, especially for severe collision scenarios