As in most structures, the principal dimensions of a ship design are usually not determined by structural considerations, but rather by more general requirements, such as beam and draft limitations, required cargo capacity, and so on. Moreover, this approach allows the designer to achieve an optimum structure, according to his own particular measure of merit, such as least life-cycle cost, least weight, or any combination of these. One of the advantages of this approach is that, unlike all earlier design methods, it applies to all types of ships.
While concept and detail design are concerned with overall requirements and standard formats, it is in preliminary design the sizing of all of the ship's principal structural members that the structural designer has the largest significant decisions and options, and the greatest scope for optimizing the design.
This sections focuses on the most complex aspects of ship structural design preliminary design.
