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Possibility of a water-transportation mode to experience numerous accidental loads is predicted limitless and always demand sustainable analysis. Impact phenomenon raises as main reason of environmental damage, for instance, grounding contributes in form of short-time impact and produces massive damage on the bottom structure of a marine vessels, e.g. ship. In this work, a series of numerical experiment is conducted with considering contribution of several parameters, namely impact location and seabed topology on the bottom structure of a tanker ship. The initial stage is conducted to obtain validation of the numerical method and configuration using impact test to ensure reliability of the present methodology which considers the finite element approach. In the second stage, proposed scenarios are calculated and overall evaluation of the damage extent is performed to observe resistance and behaviour of the bottom structure. Structural condition after grounding, rupture energy and crushing force are presented to observe history of grounding process. Contribution of the numerical parameter in form of meshing size is presented to provide adequate consideration in both of physical and numerical parameters. Finally, tendency of the target structure is summarized to provide prediction of further behaviour during the bottom structure experiences grounding with various scenarios. An alternative solution in respecting time cost is proposed and can be considered for other impact simulation and analysis.

With the opening of the Northern Sea for international shipping routes, various vessels prefer to use this option to reach Europe as distance is significantly reduced if a ship is sailing through this route. In the same time, the demand to ensure ship safety rises as impact phenomenon between ship structures and ice causes numerous casualties. This work presented a numerical study with a concentration on contact between ship structures and levels. The double side skin of a chemical tanker was modelled with a shell element while a deformable characteristic was implemented on the ice as an indenter. Several target areas on the side structure were set as impact points based on its stiffener component. Different models of indenter were taken into account in order to observe structural responses and influences of external parameters, namely ice topology, while the described location parameters were taken as the ship's internal parameters. Impact force was presented with total energy, as well as the ratio between kinetic and internal energy. The deformation pattern was used as a verification of the collision process and its subsequent results. Finally, the behavior of the inner walls subjected to type indenters was observed as this component is the final component that maintains liquid cargo and resists an impact load.

An interest in Arbitrary Lagrangian Eulerian (ALE) finite element methods has been increased due to more accurate responses in Fluid-Structure Interaction(FSI) problems. The multi-material ALE approach was applied to the prediction of the acceleration response of free-fall lifeboat, and its responses were compared to those of the single-material ALE one. It could be found that even though there was no big difference in the simulation responses of two methods, the single-material and multi-material ALE ones, the latter multi-material ALE method showed a little bit more close response to those of experimental results compared to the former single-material ALE one, especially in the x-and z-direction acceleration responses. Through this study, it could be found that several parameters in the ALE algorithms have to be examined more carefully for a good structural safety assessment of FSI problems.