Scenarios for the assessment of the collision behavior of ships

Abstract

Since the late fifties, when the first nuclear powered merchant ships were designed, collision research has been focused on the establishment of models for the prediction of the damage of the side of a ship involved in a ship-ship collision. Such models have been used to assess the performance of the struck ship in case she is involved in a collision. Further it was and it is still highly desirable to develop design tools which could provide guidance for the construction of ship hulls which will minimize as far as possible the risk in case of a collision. In order to assess the collision behaviour of a ship, there is a need to test her under specific collision incidents, which are described by a number of parameters, such as the particulars of the striking ship including the stiffness of her bow, the speeds and relative orientation of the two vessels, sea conditions, etc. The assessment methodologies are deterministic, i.e. they are based on one or a few severe collision scenarios, or probabilistic, i.e. they consider distribution functions of one or more collision parameters. The paper presents and discusses existing codes concerning collision scenarios for floating and fixed marine structures, presents data that can be used for the determination of the level of the loading that a ship may experience if she is involved in a collision and gives examples of relevant calculations.