A redundancy analysis of a semisubmersible drilling vessel operating in the North Sea was performed to determine its ability to survive a catastrophic structural failure. Different assumptions of structural failure were made, ranging from the failure of a single member to the complete loss of a joint connecting several members. For each case, a dynamic structural analysis was performed, combining static loads with rigid body dynamic loads to determine the maximum stress in each member. Wave forces acting on the vessel were represented by Morison's equation. Since drag forces are small, compared to inertia forces, they were neglected. Dynamic loads were determined for a range of wave frequencies and directions that produced the largest stress responses. Resulting stresses in critical members were computed to assess the damage.
Redundancy analysis of semisubmersible vessels operating in the North Sea
Redundanzanalyse von Halbtauchern unter den Bedingungen der Nordsee
1982
9 Seiten, 5 Bilder, 3 Tabellen, 3 Quellen
Conference paper
English