New rules for large container ships

One requirement, UR S11A three new safety measures in response to findings by Japan’s Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and the IMO following the break-up of MOL ‘Comfort’.

The effect of the lateral loads which induce bi-axial stresses of bottom shell plates is now considered in the requirements of the hull girder ultimate strength under a new IACS Longitudinal Strength Standard for Container Ships. The requirement will enter into force on 1 July 2016.

Regarding the whipping effect of hull girder loading on container ships, IACS noted that research into the area and the development of a dedicated UR would take time. Meanwhile it has introduced a ‘functional requirement’ for members to take whipping into account in their individual procdeures, from 1 July 2016.

A revised wave bending magnitude and longitudinal distribution has also been included in the development of the UR S11A.

A further requirement, UR S34, will set consistent requirements among IACS members by defining the unified minimum load cases used while performing strength assessment of container ships by Finite Element (FE) analysis. The aim is to set a higher and more unified baseline for structural strength both across the vessel and at the midship cargo hold.

UR S34 will apply only to container ships, from 1 July 2016. It requires a full-ship analysis for ships with length over 290m and a cargo hold analysis for ships with length of more than 150m.

Philippe Donche-Gay, Chairman, IACS, said: “Once again IACS has demonstrated its unrivalled technical capacity by delivering important Unified Requirements in a very tight timeframe that will further enhance large container ship safety.”