Accordingly, one of the most usual cause that results to container stack collapsing is the lack of attention to the metacentric height (GM) criteria. Placing containers with caution and a plan improves their stability, because there is the risk of an off-center weight, a negative metacentric height or a combination of both factors leading to a list, which is the permanent inclination of a ship.
A large GM leads in an increase in various forces, including racking as the rolling, the horizontal force which disrupts the ends and sides of a container. This kind of force on containers is violent and may lead to disruption. In the meantime, GM may also cause the lashing to be overloaded.
To prevent any accidents, interested parties should take into consideration the cargo securing manual, which includes guidance on increase of forces and accelerations with increase in GM, which the crew and shore planners must be aware of.
It is proposed that the approved computer programmed used for stability and lashing calculations has to cover the complete operational GM range.
A higher GM may require reduced stack weight and height and the programme should be able to advise the user of that
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