Section 5 Platings

501. Allowable stresses

Maximum allowable

3.4.1.

bending stresses in platings and stiffeners are to be in accordance with Table

Table 3.4.1. Allowable Bending Stresses

502. Minimum thickness

The thickness of structures is normally not to be mula :

less than that obtained from the following for-

mm

Yield stress in N mm at 0.2% offset for unwelded

is not to be taken greater than 70% of the ultimate tensile

strength.

: basic stiffener spacing, as following formula, however,

or greater than 1.0.

is not to be taken less than

m

and : as defined in Table

Table 3.4.2. Values of

503. Thickness of platings

1. The general requirement to thickness formula :

of plating subject to lateral pressure is given by the following

mm

correction factor for aspect ratio of plating field and degree of fixation of plate edges, giv- en in Table 3.4.3.

stiffener spacing (m ).

: design pressure, given in Ch 2, Sec 3.

allowable stress, given in Table 3.4.1.

Table 3.4.3 Values of

2. The thickness requirement for a plating field clamped along all edges with an aspect ratio ≤ 0.5 is given by the following formula :

mm

and : as given in Par 1.

3. The thickness of the bottom plating is not to be less than that obtained from the following

:

formula

mm

: correction factor for aspect ratio of plate field, as following Table 3.4.4

Table 3.4.4

: correction factor for curved plating, as following

:

:

radius of curvature (m ).

slamming pressure (kN m ), as given in Ch 2.

allowable stress (N mm ) in bottom plating, as following formula .

: stiffener span (m )

4. Above the slamming area, the thickness may be gradually reduced to the ordinary requirement at side. For craft with rise of floor, however, reduction will not be accepted below the bilge curvature or chine.