The primary objectives are to restore fidelity in the safety of container transport with the present fleet and provide the technical understanding that is needed for safe designs and innovations for the future. TopTier addresses these objectives with a wide consortium of stakeholders to ensure the required expertise and to achieve leverage for acceptance of end findings. Industry wide impact of findings and recommendations will be sought by cooperating with high-level bodies as WSC, ITF, IMO, IACS, ISO and ILO through submitting results and requesting follow-up actions.
The project approach will be around three underlying ideas:
- Accurate technical understanding and representation of ship motions and cargo securing mechanics as used in design, plan approval and operational securing calculations;
- Maximize awareness and ability of the crew to perform their operational role to keep ship motions within the (hidden) limits as used in securing calculations;
- Improve the computer calculated processes to better represent the reality on deck.
Technical issues are the aspects that are presently not yet included in the securing procedures / practices. The aim is to understand, demonstrate and recommend on how to deal with effects of extreme motions, high GM, hull girder flexibility, flexibility of containers and lashing gear components, high stack dynamics, row interactions, multi row resonance, non-linear cargo securing loads, design motion envelope statistics and realistic operating loads for containers and securing gear.
Operational aspects aim to increase awareness of actual loads in relation to the design values used in cargo calculations, probability indicators for extreme events and mitigating actions. This will be based on experience developed over the past two decades, related to parametric and synchronous roll, dynamic loss of stability, and the findings of the technical evaluations mentioned above.
The process aspects will address options and infrastructure requirements to improve tracking of container and corner casting condition, state of maintenance of the securing arrangement, and the weight, content and stuffing of the containers themselves.
SCOPE OF WORK
Presently considered scope of work includes
- On board measurements for long term ship motions, hull girder flexibility and related accelerations. Output statistics to be shared;
- In-service measurements on multi-stack-container response at selected transits;
- Desk studies and model test program on an earth quake simulator to understand high tier and multi row dynamics;
- Threat indicator for extreme motions based on measured response;
- Securing load indicator based on measured response and cargo securing calculations;
- Realistic design ratings for container and securing gear;
- Design level of probability for securing calculations;
- Stack optimisation for minimal probability of row resonance;
- Technology and required infrastructure for identification and tracking of condition and wear of container corner castings (which is essential for high stack and FAT performance).
The project consortium relies on cooperation, expertise and support from vessel and container operators, authorities and stakeholders in authorities and the industry both at sea and shore side.
The direct findings in the project will be shared with the participants. The outcome of the project will be further brought to the attention of authorities as IMO, ILO and IACS to aim for top-down implementation for a continued level and safe playing field both at sea and on shore.
The TopTier JIP is expected to run for a period of three years. An outline proposal will be circulated end February 2021. Online meetings with the interested stake holders will be held in February & March 2021 to discuss scope and tasks. The final proposal and draft Participation Agreement will be circulated in March 2021.