Page 101 - Practical Ship Design
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BEAM - METRES
Fig. 3.9. Breadth-depth relationship.
3.3.4 DrajVdepth relationship T = f(D)
This relationship, which for merchant ships embodies the freeboard rules, has
changed with alterations in these and related rules - notably the 1966 Freeboard
Convention and the 1973 IMO MARPOL rules for tankers, which are dealt with in
some detail in Chapter 1 1.
There are no freeboard rules for warships but the design needed to achieve a
high degree of seaworthiness in these ships imposes a similar constraint.
In the 1962 paper, the relationship for merchant ships was expressed as
T=2/3 [D-(h)]+K
K = 1.2 m (4 ft) for a closed shelter deck cargo ship or a tanker; K = 1.9 m (6.3 ft)
for an open shelter deck ship; h = tween deck height of open shelter deck ship.
