MULTIHULL GLOBAL LOAD CALCULATIONS ACCORDING TO ISO 12215-7
Since the end of 2019 part 7 of ISO 12215 has been finalized. This part gives besides the determination of loads also calculations for the assessment of Global Loads for multihulls.
The standard gives a simplified method, mostly to be used for cruising catamarans. Also an enhanced method is given, which provides a more accurate analysis and results and which is applicable to any structural arrangement.
Overview of Global Loads:
- Quartering sea
- Rig load
- Asymmetric broaching
- Longitudinal broaching / pitchpoling
- Longitudinal force/shock
- Bending on crossbeams of motor multihulls
For typical structure arrangements (multihulls with a significant wet deck), you can take the simplified method. According to the standard you have to check the global structure against the greater of the following two load cases:
- Combination of 100% Quartering sea + 50% Rig load or
- Combination of 50% Quartering sea +100% Rig load
We have developed a structural assessment method by making use of the following software packages:
- Hullscant Software:
for the determination of the materials and beam section properties in all kind of materials (including GRP and Carbon).
- Multiframe Software:
for the Global Load structural assessment.
FEA beam analysis software has been chosen to keep the calculations within budget. In case detailed FAE analysis are required this can be offered as well in cooperation with a partner.
On request the calculations can be extended with Global mast and rig assessments according to the requirements of ISO/FDIS 12215-10 Rig loads and rig attachment in sailing yachts.
For any questions regarding the ISO 12215-7 calculations, please feel free to contact.