Research of assessing the reliability of containers securing taking into account the actual metacentric height of the container ship

The study focuses on the impact of the metacentric height of container ships on the reliability of container securing systems in order to prevent container loss overboard, which is a significant issue in the shipping industry. It is noted that the increase in ship capacity is achieved by increasing the number of layers of containers stacked on deck. Dynamic loads on the securing means of containers stowed in the upper tiers of container stacks are increasing, that can be particularly dangerous in the intense rolling conditions. It is noted that the international shipping community is well aware of the significance of this issue and is working to develop solutions. Assessment of the expected reliability of securing systems and prevent container loss through a comprehensive analysis of relevant factors is considered. The complexity of this assessment lies in the presence of many uncertainties in the calculation algorithm. These uncertainties are supposed to be quantified taking into account the accumulated experience and statistical data within the framework of the TopTier industry project. Existing methods and calculation algorithms do not take into account the fact that the actual height of the center of gravity of containers differs from the accepted value. The goal of this article is to study the effect of the actual metacentric height of a container ship on the parameters of rolling and the loads on containers and their securing means depending on it. To do this, using the example of a real ultra large container ship, a comparative analysis of the effect of metacentric height on the rolling acceleration was performed. The effect of the rolling acceleration on the loads acting on the deck container stack has been shown. The necessity to take into account the actual height of the center of gravity of containers is justified for the correct determination the metacentric height of the container ship and calculation loads in order to ensure the safety of operation of container ships and prevent containers from being lost overboard.

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