This work deals with the influence of ship motion and deformation on the structural design of decks to support production plants in floating production and storage offloading units (FPSOs). These decks are space frames with lengths ranging from 30 to 100 meters and a variable number of rigid supports linked to the ship hull. The decks and ship hull are modeled together for naval and structural analysis. A global coupled analysis is performed considering the deck and ship structures; sea loads are evaluated by means of probabilistic methods.
Floating Production, Storage and Offloading units- FPSOs have been recently established as attractive alternatives for the exploitation of offshore oil fields. This fact is due to the versatility and economicity of this new concept, which is especially suited for deep water fields located where a pipeline network is not available, with limited recoverable reserves, and with a small number of wells. Actually, with the increasing development of this new technology, the use of FPSOs has been shown to be adequate and reliable also for the exploitation of larger oil fields. FPSOs are usually based on barges or existing tankers, converted to its new function. The main advantages of this concept are:
Integration, in one system, of all functions needed for production, storage and oil offloading to a shuttle tanker,
Flexibility in the choice of the type of ship or tanker to be employed;
Ease of installation and relocation;
Large working area, contributing to an easy arrangement of production equipments and facilities;
Simplicity of construction, with several qualified shipyards all over the world,
Tanks with large capacity for storage of the oil production;
Relatively low costs and time lag between design and production phases, especially in the case of converted tankers.
