Class NK has published a report on the incident involving the MOL Comfort, a vessel which broke in half en route through the Indian Ocean last year.
In its report, which will be submitted to Japanese government working group, The International Association of Classification Societies, ClassNK says that the vessel could have broken in half because of "lateral loads" which were acting on the double bottom structure.
However the report also says that the investigation could not find a definitive cause for the incident, citing "uncertainty factors" on the hull, such as weight of cargo, yield stress of steel and sea states, which could have contributed in varying degrees.
Despite this, ClassNK states: “The investigation concluded that the load of the vertical bending moment exceeded the hull girder ultimate strength at the time of the accident when the effects of the deviations of the uncertainty factors were taken into account, although the overlap between the strength and the load was very narrow."
As part of the report ClassNK said it was taking a number of actions to ensure structural safety of post-panamax container ships of 8,000 teu class. It will assess a ship’s strength margin by evaluating hull girder ultimate strength through working out and understanding the effects of “lateral loads”, and also by evaluating the stiffened bottom panels for their buckling collapse strength.
Head over to ClassNK to read the full report.