What is the required total area under the GZ curve up to the angle of down flooding for container ships?

The required total area under the GZ curve up to the angle of down flooding for container ships must be not less than 0.029/C m.radians, as specified in stability criteria for these vessels. This value is crucial because it ensures that the ship maintains adequate stability in the event of heel due to external forces, helping to prevent capsizing.

The GZ curve represents the righting arm (GZ) as a function of the angle of heel. The area under this curve up to the downflooding angle is indicative of the ship’s ability to right itself and stay upright against heeling moments. If the area is less than the required threshold, it suggests insufficient stability, potentially leading to loss of vessel integrity in adverse conditions.

In the context of container ships, which can experience significant changes in stability as cargo is loaded or offloaded, maintaining the required area ensures safety and compliance with stability regulations. The use of the calculated threshold aids in assessing the vessel’s performance during its operational lifetime, especially considering dynamic conditions that may affect stability.