Validation of Twistlocks in Modular Offshore Platform Designs for the Arctic

The University of Rostock has generated dimensioning equations to calculate the strength of twistlock systems under non-standard loading conditions on offshore platforms in the POLAR project in the last years. These dimensioning equations have been presented on previous OMAE conferences. In this paper ultimate strength analyses are conducted to assess the safety margin between elastic design and final rupture. The validation of the local system is shown and the results of the experiment and the simulation are analyzed and compared. In these experiments twistlock systems are subjected to cyclic loads, long-term tensile load at design level and ultimate loads. The experiments are conducted with a heavy duty hydraulic test rig. The results show agreement between experiment and simulation with regard to the rupture behavior and the force-displacement relationship.