(1) The sheer shall be measured from the deck
at side to a line of reference drawn parallel to the keel through
the sheer line amidships.
(2) In ships designed with a rake of keel, the
sheer shall be measured in relation to a reference line drawn parallel
to the design load waterline.
(3) In flush deck ships and in ships with detached
superstructures the sheer shall be measured at the freeboard deck.
(4) In ships with topsides of unusual form in
which there is a step or break in the topsides, the sheer shall be
considered in relation to the equivalent depth amidships.
(5) In ships with a superstructure of standard
height which extends over the whole length of the freeboard deck,
the sheer shall be measured at the superstructure deck. Where the
height exceeds the standard, the least difference (Z) between the
actual and standard heights shall be added to each end ordinate. Similarly,
the intermediate ordinates at distances of 1/6L and 1/3L from each
perpendicular shall be increased by 0.444Z and 0.111Z, respectively.
Where there is an enclosed poop or forecastle superimposed on the
superstructure, sheer credit shall be allowed for such a poop or forecastle,
according to the method of paragraph (12) as shown in figure 38.1.
Figure 38.1
(6) Where the deck of an enclosed superstructure
has at least the same sheer as the exposed freeboard deck, the sheer
of the enclosed portion of the freeboard deck shall not be taken into
account.
(7) Where an enclosed poop or forecastle is of
standard height with greater sheer than that of the freeboard deck,
or is of more than standard height, an addition to the sheer of the
freeboard deck shall be made as provided in paragraph (12).
Where a poop or forecastle consists of two layers, the method
shown in figure 38.2 shall be used.
Figure 38.2
In figures 38.1 and 38.2, the following definitions apply:
Z |
= |
is as defined in paragraph (5);
and |
Zv
|
= |
is the end ordinate
of a virtual standard parabolic curve taken through the point "X".
If Zv is greater than (Z + h), the end ordinate shall be
(Z + h), in which case point "X" shall be disregarded and curve (2)
not taken into account.
|
When the length of the first tier superstructure is greater
than 0.5l, the virtual standard parabolic curve shall
commence at amidships as indicated in figure 38.1.