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This work made a comparison of the effects of selected element formulations (EFs) through nonlinear finite element analysis (NLFEA) and physical configurations in scenario design, particularly target locations. The combined results help in quantifying structural performance, focusing on crashworthiness criteria. The analysis involves nonlinear dynamic finite element methods, using an explicit approach applied to an idealized system. This system models ship-to-ship collisions, specifically the interaction between Ro and Ro and cargo reefer vessels, with one striking the other. Summarizing initial NLFEA results reveals that the chosen EF significantly influences the crashworthiness criteria. Notably, differences in formulations lead to different calculation times. The Belytschko–Tsay (BT) EF is the quickest, followed by the Belytschko–Leviathan (BL), with around a 36% difference. Conversely, formulations such as the Hughes–Liu involve much longer processing times, more than twice that of BT. To address the potential impact of shear locking and hourglassing on calculation accuracy during impact, the fully integrated (FI) version of the EF is used. It mitigates these undesired events. For formulations with the same approach, the FI BT formulation suppresses hourglassing effectively, unlike others that show orthogonal hourglassing increments. To ensure reliability, rules were set to assess hourglassing. The criterion is that the ratio of hourglass energy to internal energy should be ≤10%. All formulations meet this criterion and are suitable as geometric models in NLFEA. Regarding reliability and processing time, analyzing the computation time offers insights. Based on calculations, BL is the fastest, followed by Belytschko–Wong–Chiang, while the FI BT formulation takes more time for the same collision case.

Ship collision appears as the most threatening loading accounting for structural casualties and numbers of casualties after impact on the target ship. In order to avoid such losses against collision, better safety during activities in maritime environment is demanded. Therefore, assessment of ship structure is needed to understand dynamic effect of the impact and quantify nonlinear behavior of local members. This study is conducted to achieve those aims by deploying nonlinear finite element analysis (NLFEA) to idealized ship collision event. Validation of the numerical method is performed by comparing results of a modeled collision case with various empirical calculations. Design for impact loading in main analysis considers side collision to main hull structure, which single side skin (SSS) and double side skin (DSS) types are modeled. Investigation is also directed to influence of the target members on the main hull to capacity of absorbed energy and characteristic of structural resistance. Analysis results indicate that good understanding is successfully obtained in terms of structural damage-energy relation. Confirmation of the current calculation using numerical calculation is also confirmed considering the modeled cases and empirical results agree well. Tendency of hull responses concluded that the longitudinal members contribute more to structural resistance against side collision.

The main goal of the present paper was to study the physical response of a double side skin (DSS) structure under impact load in a collision event between two ships. Collision energy and damage extent (size and location) during the collision process were observed together with damage patterns on side structure. The ships were modeled after a Ro-Ro passenger ship and cargo reefer which were involved in a ship collision on the Sunda Strait while the analyseswere performed using non-linear simulations FEMto produce virtual simulation data. Several caseswere proposed to be investigated in this work with involvement of parameters i.e. penetration location and ship materials which were embedded on the structure model. A series of material experiments and testing was conducted to obtain detailed material properties which were to be deployed in simulation. It was shown that, after penetration at the transition location, the striking ship was successfully deforming and forming tears to the inner skin. On the other hand, with identical structure and identical mass of construction, the use of high-strength low-alloy (HSLA) steel as the repair material offered considerably better capacity in absorbing the impact load than plain-carbon steel.