Characteristics of material, ship side structure response and ship survivability in ship collisions

Research on ship collision and grounding has taken giant steps during the last decade. One reason is that computer capacity has increased and, therefore, also the possibility to simulate various collision scenarios in a realistic way using more advanced and larger models. As a result, it has been possible to investigate in more detail the understanding of structural integrity, characteristics and failure phenomena that interact during, for example, a collision. This article summarises research experiences from a research group that has been working with ship collision safety, using both experiments and numerical simulations by finite element (FE) analysis. Results are presented from tensile and forming limit tests, followed by FE analyses of these with the objective of predicting material rupture using appropriate constitutive material models and damage criteria. An example of an innovative design of a side-shell structure that is considered to be more intrusion-tolerant than most side-shell structures used today is demonstrated. Finally, results from a research project which has a holistic approach on the assessment of survivability of a struck ship are presented. In the project, a methodology has been developed which combines structural analysis and damage stability analysis followed by risk analysis.